Abstract:
A stable, self-standing, taco shell is provided. The taco shell has a first sidewall element, a second sidewall element, a substantially flat base element of defined width, a first curved element interconnecting the first sidewall element to the flat base element; and a second curved element interconnecting the second sidewall element to the flat base element. Methods of fabrication and use are disclosed.

Description:
PRIORITY CLAIM 
       [0001]    The present patent application is a continuation of U.S. patent application Ser. No. 10/501,298, filed Jul. 12, 2004, entitled SQUARE BOTTOM TACO SHELL, which is the National Stage of International Application No. PCT/US02/36474, filed on Nov. 14, 2002, and having a PCT Publication No. WO 2004/043154, entitled SQUARE BOTTOM TACO SHELL, wherein all prior patent applications are commonly owned by the owner of the present patent application and wherein the entire contents of said applications and prior patent applications are incorporated herein by reference for all purposes. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to an edible food shell. More specifically, the present invention relates to a taco shell. 
       BACKGROUND OF THE INVENTION 
       [0003]    A conventional taco shell is formed by placing a circular tortilla in a U-shaped mold. The tortillas used for conventional tacos are typically between 5.0 and 7.5 inches in diameter. Once the tortilla has taken on the shape of the mold, the tortilla is made generally rigid by baking or deep fat frying. The resulting taco shell  10  is U-shaped when viewed from the end (see  FIG. 1 ). 
         [0004]    As shown in  FIG. 1 , a conventional taco shell  10  will have a pair of opposed sidewalls  15  that are interconnected by a generally semi-circular or round base  20 . Often, each sidewall  15  diverges from the vertical centerline of the shell  10  by approximately 25 degrees, as indicated by angle “A” in  FIG. 1 . The top edge  25  of each sidewall  15  is free of connection to the opposing sidewall  15 , creating the open end  30  of the shell  10 . The sidewalls  15  and base  20  define a cavity  35  in which taco filling (e.g., lettuce, beans, cheese, cooked meat or poultry or the like) is placed. 
         [0005]    As can be seen in  FIG. 1 , the base  20  of the conventional taco shell  10  is relatively narrow as compared to the height of the shell  10 . The conventional taco shell&#39;s configuration and narrow base  20  prevent taco consumers from filling the cavity  35  with preferred amounts of meat without overly limiting the space available for other types of taco filling. For example, if a consumer puts in more than minor amounts of meat, the remaining space within the cavity  35  is insufficient to allow the inclusion of adequate amounts of other available fillings like lettuce, cheese, tomatoes, black olives, sour cream, etc. Another problem is that the narrow base  20  prevents a utensil (e.g., a spoon) from being placed near the base of the taco shell  10  when used to fill the taco shell  10  with meat or other filling. 
         [0006]    Another problem presented by the configuration of the conventional taco shell  10  is that the shell  10  tends to fail at the base  20 . When this occurs, the shell  10  no longer retains the taco filling. Consequently, the taco filling, especially the liquid elements like taco sauce and meat juices, escape from the taco shell  10  making a mess. 
         [0007]    Another problem presented by the configuration of the conventional taco shell  10  is that the narrow, rounded base  20  prevents the taco shell  10  from being stable in an upright position. Consequently, when not being held, a conventional taco shell  10  must be laid on its side to prevent the shell  10  from tipping over. However, when the taco shell  10  is on its side, the shell  10  can no longer hold the taco filling, which spills out through the open end  30  of the shell  10 . 
         [0008]    In order to hold taco shells upright, various taco shell holders have been devised. Typically, the taco shell holder has a body with a wide base and a taco shell receiving opening in which the taco shell sits while it is filled with the taco filling. However, the taco shell holders are not edible and, therefore, generate a significant amount of waste. Furthermore, in the fast-food-take-out environment, taco shell holders make it difficult to package the taco shell when the taco shell is filled with taco shell filling. Supplemental packaging such as taco stands adds costs as well. 
         [0009]    There is a need in the art for a taco shell that is capable of standing without assistance whether initially or partially consumed. Also, there is a need in the art for methods for manufacturing and using such a taco shell. 
       BRIEF SUMMARY OF THE INVENTION 
       [0010]    The present invention, in several embodiments, is a stable, self-standing, taco shell. In one embodiment the stable, self-standing, taco shell has a first sidewall and a second sidewall interconnected by a substantially flat base. The taco shell is configured so the height of the taco shell is approximately 1.50 to 4.0 times the width of the base. 
         [0011]    In one embodiment, the stable, self-standing, taco shell has a first sidewall and a second sidewall interconnected by a substantially flat base. The taco shell is configured so that the height of the taco shell is approximately about 50-110 millimeters (2.0 to 4.0 inches) and the width of the base is at least 10-15 millimeters (0.50 inch). In another embodiment, the width of the base is at least 19 millimeters (about 0.75 inch). In yet another embodiment, the width of the base is approximately 25 mm (about 1.0 inch). 
         [0012]    In one embodiment, the stable, self-standing, taco shell has a first sidewall element, a second sidewall element, a substantially flat base element, a first curved element interconnecting the first sidewall element to the flat base element, and a second curved element interconnecting the second sidewall element to the flat base element. In one embodiment of this taco shell, at least one of the elements will have a thickness of at least 1.5 millimeters. In one embodiment of this taco shell, at least one of the elements will have a thickness of less than 1.5 millimeters. In other embodiments of this taco shell, the curved elements may have large, medium or small radii. 
         [0013]    The present invention, in several embodiments, further resides in methods of making a stable, self-standing, taco shell. In one embodiment, the method entails providing a soft flexible uncooked or partially cooked tortilla and placing the tortilla in or on a mold. The mold is configured so the resulting taco shell has a first sidewall and a second sidewall interconnected by a substantially flat base, and the height of the resulting taco shell is approximately 1.50 to 4.0 times the base width of the taco shell. 
         [0014]    In one embodiment, the present methods of making a stable, self-standing, taco shell involves providing a tortilla and placing the tortilla into or on a mold. The mold is configured so the resulting taco shell has a first sidewall element, a second sidewall element, a substantially flat base element, a first curved element interconnecting the first sidewall element to the flat base element, and a second curved element interconnecting the second sidewall element to the flat base element. In one embodiment of this method, at least one of the elements will have a thickness of at least 1.5 millimeters. In one embodiment of this method, at least one of the elements will have a thickness of less than 1.5 millimeters. In other embodiments of this method, the curved elements may have large, medium or small radii. 
         [0015]    The present invention, in several embodiments, is a method of using a stable, self-standing, taco shell. The method involves locating a flat preparation surface and selecting at least one stable, self-standing, taco shell having a first sidewall and a second sidewall interconnected by a substantially flat base, the taco shell configured so the height of the taco shell is approximately 1.50 to 4.0 times the width of the base. The at least one taco shell is then placed upright on the preparation surface and filled with taco filling. 
         [0016]    In one embodiment, the method of using a stable, self-standing, taco shell entails locating a flat preparation surface and selecting at least one stable, self-standing, taco shell having a first sidewall element, a second sidewall element, a substantially flat base element, a first curved element interconnecting the first sidewall element to the flat base element, and a second curved element interconnecting the second sidewall element to the flat base element. The at least one taco shell is then placed upright on the preparation surface and filled with taco filling. In one embodiment of this method, at least one of the elements will have a thickness of at least 1.5 millimeters. In one embodiment of this method, at least one of the elements will have a thickness of less than 1.5 millimeters. In other embodiments of this method, the curved elements may have large, medium or small radii. 
         [0017]    While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. As will be realized, the invention is capable of modifications in various obvious aspects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]      FIG. 1  is an end elevation view of a conventional U-shaped taco shell. 
           [0019]      FIG. 2  is an isometric view of a self-standing taco shell having a substantially flat base and sitting upright on a flat preparation surface. 
           [0020]      FIG. 3   a  is an end elevation view of the self-standing taco shell of  FIG. 2  having large radius curved segments. 
           [0021]      FIG. 3   b  is an end elevation view of the self-standing taco shell of  FIG. 2  having medium radius curved segments. 
           [0022]      FIG. 3   c  is an end elevation view of the self-standing taco shell of  FIG. 2  having small radius curved segments. 
           [0023]      FIG. 3   d  is an end elevation view of the self-standing taco shell of  FIG. 2  after the shell has failed at one of the shell&#39;s two curved segments. 
           [0024]      FIG. 4  is an isometric view of a self-standing food trough having a substantially flat base and sitting upright on a flat preparation surface. 
           [0025]      FIG. 5  is an end elevation view of the self-standing food trough of  FIG. 4 . 
           [0026]      FIG. 6  is a flow chart illustrating a method of manufacturing a self-standing taco shell having a substantially flat base. 
           [0027]      FIG. 7  is a flow chart illustrating a method of using a self-standing taco shell having a substantially flat base. 
           [0028]      FIG. 8  is an isometric view of a tray having a surface that may be used to further stabilize the taco shell of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0029]      FIG. 2  is an isometric view of a self-standing taco shell  110  formed from a circular tortilla.  FIG. 2  depicts the taco shell  110  sitting upright, without assistance, on a flat preparation surface  112 . 
         [0030]      FIG. 3   a  is an end elevation view of the same self-standing taco shell  110  shown in  FIG. 2 . As shown in  FIG. 3   a , the taco shell  110  includes a pair of opposed sidewalls  115  that are interconnected by a flat base  120 . The top edge  125  of each sidewall  115  is free of connection to the opposing sidewall  115 , creating the open end  130  of the shell  110 . The sidewalls  115  and base  120  define a cavity  135  in which taco filling (e.g., lettuce, beans, cheese, cooked meat or poultry or the like) is placed. 
         [0031]    The base  120  comprises a flat segment  140 , which is bordered by two curved segments  145 . Each curved segment  145  serves as a transition from the base  120  to a sidewall  115 . In one embodiment of the invention, as reflected in  FIG. 3   a , the radii of the curved segments are large (approximately 6 millimeters or greater), forming rounded transitions from the base  120  to the sidewalls  115 . In one embodiment of the invention, as shown in  FIG. 3   b , the radii of the curved segments  145  are medium (approximately 6 millimeters to 3 millimeters). In one embodiment of the invention, as indicated in  FIG. 3   c , the radii of the curved segments are small (approximately 3 millimeters or less), forming transitions from the base  120  to the sidewalls  115  that have a profile with a very pronounced edge. As a general rule, the larger the radius of a curved segment  145 , the less likely the shell  110  will fail at that curved segment  145 . 
         [0032]    As indicated in  FIG. 3   a , each sidewall  115  can diverge from the vertical centerline of the shell  110 . Potential angles of divergence range from about zero to about 25 degrees, as indicated by angle “A” in  FIG. 3   a.    
         [0033]    Excessive angles of divergence “A” in conventional taco shells  10  cause taco consumers to close or pinch the top edges  25  of the shell  10  together, bringing about taco shell failure. To overcome this problem, some embodiments of a taco shell of the present invention may include less divergence than that of a conventional taco. For instance, one embodiment of the taco shell  110  has a base width (represented by letters “Db” in  FIG. 3   a ) of approximately 19 to 32 millimeters (about 0.75 to 1.25 inches) while the open end width (represented by letters “De” in  FIG. 3   a ) is approximately 32 to 35 millimeters (about 1.25 to 1.375 inches). In another embodiment, the base width Db is approximately 19 to 39 millimeters (about 0.75 to 1.5 inches) and the open end width De is approximately 35 to 44 millimeters (about 1.375 to 1.75 inches). In another embodiment, the base width Db is approximately 19 to 39 millimeters (about 0.75 to 1.5 inches) and the open end width De is approximately 44 to 51 millimeters (about 1.75 to 2.0 inches). Finally, in yet another embodiment, the base width Db is approximately 25 millimeters (about 1.0 inch) and the open end width is approximately 39 millimeters (about 1.5 inches). 
         [0034]    As shown in  FIG. 3   a , in one embodiment of the invention, the flat base  120  of the taco shell  110  is wider than the rounded base  20  of the conventional taco shell  10  illustrated in  FIG. 1 . The base  120  of the taco shell  110  has been increased so that the height (represented by letters “Dh” in  FIG. 3   a ) of the shell  110  is now approximately 1.50 to 4.0 times the base width Db. Because of its width Db, the base  120  of the taco shell  110  is able to overcome the destabilizing effect presented by the normal variations in the surface topography of a taco shell  110 . Thus, the base  120  allows the taco shell  110  to stand upright without assistance when the taco shell  110  is being filled with taco filling. Also, the base  120  allows a taco, which has been partially consumed, to stand upright without assistance. 
         [0035]    In one embodiment, the taco shell  110  has a height of approximately 51 to 65 millimeters (about 2.0 to 2.5 inches), a base width Db of approximately 19 to 32 millimeters, and an open end width De of approximately 32 to 39 millimeters. This taco shell&#39;s relatively narrow open end width De and its low height Dh to base width Db ratio results in a self-standing taco shell  110  that is especially stable in the upright position. This taco&#39;s relatively broad flat base  120  allows the taco shell  110  to successfully over come the destabilizing effect presented by the normal variations in the surface topography of a taco shell. 
         [0036]    In one embodiment of the invention, the base width Db of the taco shell  110  is such that the taco height Dh is less than 4.0 times the base width Db. In another embodiment, the height Dh of the taco shell  110  is approximately 1.75 to 3.35 times the base width Db. In yet another embodiment, the height Dh of the taco shell  110  is approximately 2.0 to 3.0 times the base width Db. Finally, in another embodiment, the height Dh of the taco shell  110  is approximately 2.0 to 2.5 times the base width Db. 
         [0037]    In one embodiment of the invention, the height Dh of the taco shell  110  is approximately 51 to 102 millimeters (about 2.0 to 4.0 inches) while the base width Db is at least approximately 12 millimeters (about 0.50 inch). In another embodiment, the height Dh of the taco shell  110  is approximately 51 to 102 millimeters while the base width Db is at least approximately 16 millimeters (about 0.65 inch). In yet another embodiment, the height Dh of the taco shell  110  is approximately 51 to 102 millimeters while the base width Db is at least approximately 19 millimeters. In yet another embodiment, the height Dh of the taco shell  110  is approximately 51 to 102 millimeters while the base width Db is at least approximately 21 millimeters (about 0.85 inch). Finally, in another embodiment, the height Dh of the taco shell  110  is approximately 51 to 102 millimeters while the base width Db is at least approximately 25 millimeters. 
         [0038]    In one embodiment of the invention, the height Dh of the taco shell  110  is approximately 57 to 77 millimeters (about 2.25 to 3.0 inches) and the base width Db is at least approximately 16 millimeters. In one embodiment of the invention, the height Dh of the taco shell  110  is approximately 57 to 70 millimeters (about 2.25 to 2.75 inches) and the base width Db is at least approximately 19 millimeters. In one embodiment of the invention, the height Dh of the taco shell is approximately 57 to 70 millimeters and the base width Db is at least approximately 21 millimeters. In one embodiment of the invention, the height Dh of the taco shell is approximately 57 to 70 millimeters and the base width Db is at least approximately 25 millimeters. 
         [0039]    In one embodiment of the invention, the base width Db of the taco shell  110  is no wider than the distance an average adult mouth may comfortably open when consuming a taco. In one embodiment, the base width Db is approximately 25 millimeters. In another embodiment, the base width Db of the taco shell  110  is no wider than the distance an average child mouth may comfortably open when consuming a taco. 
         [0040]    A comparison of the taco shell  110  (illustrated in  FIG. 3   a ) to the conventional taco shell  10  (illustrated in  FIG. 1 ) shows the cavity  135  of the taco shell  110  is larger than the cavity  35  of the conventional taco shell  10 . Consequently, the taco shell  110  can hold a greater amount of taco filling than the conventional taco shell  10 . This is advantageous because the taco shell  110  can be filled with greater amounts of meat and still have room for adequate amounts of all other available fillings. Typically, a taco shell filled with adequate amounts of meat and all other available fillings will have greater flavor and, as a result, will be preferred by a taco consumer. Another advantage of the taco shell  110  is that the larger cavity  135  and base  120  allow a utensil (e.g., spoon) to be used to access the base of the taco shell  110  when used to load the taco shell  110  with taco filling. 
         [0041]    The configuration of the taco shell  110  (shown in  FIGS. 3   a ,  3   b  and  3   c ) causes the shell  110  to fail primarily at one of its two curved segments  145 . This failure occurs primarily at these segments because stress concentrations arise at the curved segments  145 . The smaller the radius of a curved segment  145 , the greater the stress concentration therein and the more likely the shell  110  will fail at that location. 
         [0042]    As shown in  FIG. 3   d , when one of the two curved segments  145   a ,  145   b  fails, a L-shaped shell section  150  remains. The L-shaped shell section  150  comprises the flat segment  140  and one sidewall  115   b  joined by the remaining unbroken curved segment  145   b . Since the resulting L-shaped shell section  150  has a sidewall  115   b  connected to the flat segment  140 , the shell  110  can still retain the taco filling  155 , including any taco sauce and meat juice. Thus, unlike a conventional taco shell  10 , the taco shell  110  can retain its filling  150  though the shell  110  has failed. 
         [0043]    As indicated in  FIG. 3   d , the free sidewall  115   a  slides towards the other sidewall  115   b  until its progress is arrested by the taco filling  155  contained in the cavity  135 . The taco can then be consumed like a sandwich. 
         [0044]    Because the taco shell  110  can fail at one of its curved segments  145  and still retain the taco filling  155 , preventing the failure of the taco shell  110  is less of a concern than it is with the conventional shell  10 . Consequently, in one embodiment of the invention, the taco shell  110  may be made from a tortilla having a thickness (“Ts” in  FIG. 3   d ) of less than 1.5 millimeters (i.e., a thin tortilla). 
         [0045]    To reduce the likelihood of shell failure, conventional taco shells  10  are made from tortillas having a thickness (“Ts” in  FIG. 1 ) of 1.5 millimeters or greater. Thus, the taco shell  110  made from the “thin tortilla” is advantageous over the conventional taco shell  10  because less dough is required for each taco shell  110 . Also, since some fried taco shells are high in fat content, the consumer ingests less fat per taco when the taco shell  110  is made from a “thin tortilla.” Also, with the “thin tortilla” embodiment, more taco shells can be provided for a given package weight. Conversely, for the same number of taco shells, ingredient amounts and costs are lowered for the “thin tortilla” embodiment over the embodiment having a thicker tortilla thickness. 
         [0046]    The taco shell  110  of the present invention may be made using a tortilla having a thickness less than 1.5 millimeters or a thickness greater than or equal to 1.5 millimeters. Consequently, in one embodiment, the taco shell  110  can be made from a standard tortilla having a thickness Ts of approximately 1.5 to 3.0 millimeters or greater. 
         [0047]      FIG. 4  is an isometric view of an alternative embodiment of the self-standing taco shell  110  called the self-standing food trough  160 .  FIG. 4  depicts the food trough  160  sitting upright, without assistance, on a flat preparation surface  112 . 
         [0048]    In one embodiment, the food trough  160  is formed from a circular tortilla in a manner as outlined in  FIG. 6  and discussed below. In another embodiment, the food trough  160  is actually a cookie or cracker. This embodiment is made by cooking cracker or cookie dough in molds configured like the food trough  160  in  FIG. 4 . 
         [0049]    The food trough  160  can be made in many different sizes. Generally, the food trough  160  is longer (the length depicted in  FIG. 4  by the dimension D 1 ) than it is wide (the width depicted in  FIG. 5  by the dimension Db). 
         [0050]      FIG. 5  is an end elevation view of the same self-standing food trough  160  shown in  FIG. 4 . As shown in  FIG. 5 , the food trough  160  includes a pair of opposed sidewalls  162  that are interconnected by a flat base  164 . The top edge  166  of each sidewall  162  is free of connection to the opposing sidewall  162 , creating the open end  168  of the trough  160 . The sidewalls  162  and base  164  define a cavity  170  in which an edible filling is placed. 
         [0051]    The base  164  comprises a flat segment  172 , which is bordered by two curved segments  174 . Each curved segment  174  serves as a transition from the base  164  to a sidewall  162 . In one embodiment of the trough  160 , its curved segments  174  will have ranges of radii similar to those of the taco shell  110 . The trough  160  have a range for angles of divergence (represented by angle “A” in  FIG. 5 ) that are similar to those of the taco shell  110 . 
         [0052]    In one embodiment of the food trough  160 , its height Dh will be less than the height Dh of the taco shell  110 . In another embodiment, the height Dh of the food trough  160  will be limited to the distance an average adult mouth can comfortably open when consuming a sandwich. In another embodiment, the height Dh of the food trough  160  will be limited to the distance an average child mouth can comfortably open when consuming a sandwich. In yet another embodiment, the height Dh of the food trough will be approximately 12 to 25 millimeters (about 0.50 to 1.0 inch). 
         [0053]    In the large embodiment of the food trough  160 , its base width Db will be at least approximately 25 millimeters. In another embodiment, the base width Db of the food trough  160  will be limited to the bite width of an average adult mouth. In another embodiment, the base width Db of the food trough  160  will be limited to the bite width of an average child mouth. In yet another embodiment, the base width Db of the food trough  160  will be approximately 25 millimeters to 51 millimeters. 
         [0054]    The length of the food trough  160  can be varied. In one embodiment, the length will be about 127 millimeters (about 5 inches). 
         [0055]    These embodiments are advantageous because the food trough  160 , when used as a taco shell, allows the taco to be eaten like a hot dog. As a result, a taco consumer may eat a taco without having to tilt his or her head to the right or left, as is typically required when eating a taco in a conventional taco shell  10 . 
         [0056]    A process of making the self-standing taco shell  110  will now be described by referring to the process flow chart illustrated in  FIG. 6 . Initially, masa dough is formed. As one of ordinary skill in the art would recognize, this may be done by purchasing masa dough from a vendor, purchasing masa flour and mixing it with water, annatto (an optional yellow coloring), salt and rework to form the dough (block  200 ), or by purchasing raw corn and processing it to make the masa dough. If raw corn is purchased, the raw corn is cooked with lime and then steeped. The corn is then washed and ground into masa flour, which is then mixed with other ingredients to form the dough. The dough enters the sheeting machine, which forms raw masa tortillas (block  210 ). In one embodiment of the invention, the tortillas will have a thickness of less than 1.5 millimeters. In another embodiment of the invention, the tortillas will have a thickness of approximately 1.5 to 3.0 millimeters or greater. Also, while the present invention finds particular suitability for use in connection with the provision of corn or maize based masa flour, the skilled artisan will appreciate that the present invention finds usefulness in provision of wheat or wheat/corn blends based formed taco shells. 
         [0057]    The raw masa tortillas can optionally then be flash baked, resulting in raw masa tortillas with toast marks (block  220 ) as well as a reduced moisture content so as to thereby minimize fat take-up during the subsequent frying step. The toasted still soft and flexible tortillas are then formed into self-standing taco shells having substantially flat bases (block  230 ). 
         [0058]    During the forming process, the tortillas are placed on molds and the tortillas conform to the molds (block  230 ). The molds can be a wire mesh mold, a wire cage mold, a combination wire mesh/cage mold, or a conventional mold having upper and lower plates. In either case, the molds are flat-bottomed and have cross-sectional elevations like the self-standing taco shells  110  shown in  FIGS. 3   a ,  3   b  and  3   c  and as discussed above. Like the taco shells  110  illustrated in  FIGS. 3   a ,  3   b  and  3   c , the curved segments of the mold may have large, medium or small radii as discussed above. 
         [0059]    The conformed tortillas are then fried and adopt the form of the molds (block  240 ). The tortillas exit the fryer as fried self-standing taco shells having substantially flat bases and a moisture content of less than about 6%. Optionally, the fried tacos can be partially defatted by oil draining and/or hot air oil removal. Since the formed tacos are still plastic or pliable for short periods while still hot immediately after frying, care should be taken to preserve the desired square bottomed shape. Oil is allowed to drain from the taco shells as they cool (block  250 ) and harden. In another embodiment, the tortillas are baked to a final moisture content of less than 6% to form low fat shaped rigid tacos. A number (e.g., 3-6) of the cooled hardened rigid taco shells are then nested (block  260 ) together into nested quantities and these nested quantities preferably provided with an intermediate spacer (not shown) and packaged (block  270 ) such as by providing one or more of the nested quantities onto a support board and then a film over wrap. 
         [0060]    Minimizing the formation of discontinuities (e.g., bubbles and voids) in a taco shell can be a challenge when commercially producing taco shells. Discontinuities in taco shells can be minimized by providing masa flour of the proper granulation, using the proper ratios of ingredients, maintaining the proper moisture level in the dough, baking and frying properly, and avoiding the use of taco shell molds having complex geometries. Because the flat-bottomed molds have simple geometric characteristics, the tortillas readily conform to the molds, minimizing the potential for the formation of destabilizing discontinuities, especially those at the base  120  of the shell  110 . 
         [0061]    A method of using a self-standing taco shell  110  having a substantially flat base  120  will now be described by referring to the process flow chart illustrated in  FIG. 7 . A flat preparation surface  112  is located (block  300 ). One or more self-standing taco shells  110 , having substantially flat bases  120  and characteristics as discussed above and illustrated in  FIGS. 3   a ,  3   b  and  3   c , are selected (block  310 ) and placed upright on the flat preparation surface  112  (block  320 ). Alternatively, one or more self-standing taco shells  110 , having substantially flat bases  120  and characteristics as discussed above and illustrated in  FIGS. 3   a ,  3   b  and  3   c , are selected (block  310 ) and simply held or supported in an upright position. Each shell  110  is then filled with taco filling (e.g., lettuce, beans, cheese, cooked meat or poultry, sauce, sour cream, guacamole, or the like) (block  330 ). For example,  FIG. 8  shows a tray  400  that may be used in conjunction with the taco shell  110  of the present invention to prepare tacos, store tacos, or present tacos to consumers. The tray  400  has a surface  402  upon which a taco shell  110  can be placed. The tray also has a structure  404  that provides at least one support surface  406 . The surfaces  402  can be sized by appropriately spacing the structures  404  such that the support surfaces  406  further stabilize the taco shell  110  when it is in a standing position. As such, while the taco shell  110  is a stable, self-standing structure, depending on the environment, one or more support surfaces  406  may be used to further stabilize the taco shell  110  during preparation of the tacos for storing tacos, or for presentation of the tacos for sale. 
         [0062]    In one embodiment of the invention, the taco shell  110  is reheated prior to being filled with heatable taco filling (i.e., meat, poultry or bean filling). In another embodiment, heatable filling is placed in the taco shell  110  and then preheated. In another embodiment, an individual or machine fills one or more taco shells  110  with heatable filling and then leaves the one or more tacos in an upright position for another individual to or machine to fill with other types of taco filling. Finally, in one embodiment, an individual or machine leaves one or more taco shells  110  in an upright position for another individual or machine to fill with taco filling. 
         [0063]    The self-standing taco shell  110  makes it easier to prepare multiple tacos at the same time. This advantage is especially desirable in fast food, cafeteria and party environments where multiple tacos are being prepared at one time. 
         [0064]    Still another advantage of the present tacos is that even if taco breakage occurs along either connection between flat base and sidewall, the flat base and remaining sidewall forms a ledge minimizing loss of the added fillings to allow for consumption completion with reduced mess. 
         [0065]    Also, another advantage of a taco made using the taco shell  110  of the present invention may be presented for consumption in an upright and filled orientation. 
         [0066]    Although the present invention has been described with reference to preferred embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.