Composed element, which comprises two panel-shaped elements (2a, 2b), each with respective panel surfaces (6a, 7a, 6b, 7b), wherein for each of the two panel-shaped elements (2a, 2b) a center line (Ma, Mb) is defined centrally between the two panel surfaces (6a and 7a, 6b and 7b) of that panel-shaped element (2a, 2b); wherein said panel-shaped elements (2a, 2b) are manufactured of wood-based material; wherein said panel-shaped elements (2a, 2b) are configured such that they can be coupled to each other at an angle by means of a locking tongue and groove connection and thereby respectively form a connection, an inner corner and outer corner, wherein the inner corner and outer corner define a theoretical miter line; wherein said locking tongue and groove connection respectively is formed of a tongue on one of said panel-shaped elements, of a groove on the other of said panel-shaped elements, and of locking elements (10, 11) provided on said tongue and groove; wherein the panel-shaped elements (2a, 2b) are configured such that they can be coupled to each other laterally and at an angle by means of a turning movement and/or a snap movement to form said connection; wherein, seen in cross-section, the panel surface (6a, 6b) of each of the two panel-shaped elements (2a, 2b) at the side of the formed outer corner in the connection extends at least up to the center line (Mb, Ma) of the panel-shaped element (2b, 2a) to which it is coupled; wherein said locking elements (10, 11) are only present at the height of one side of the tongue; wherein said tongue is cut free on at least one side by means of a narrow incision, wherein by a narrow incision, an incision is meant having a depth which is larger than the width; wherein by cut free is meant freed from still present surrounding material of the respective panel-shaped element; wherein said groove, on at least one side thereof, seen in cross-section, is bordered by a protruding lip extending to beyond said theoretical miter line, seen from the panel-shaped element comprising the groove; wherein said protruding lip is located at the side which is situated closest to the formed outer corner; wherein at the height of this protruding lip at least one contact surface (17, 18) is formed between the tongue and the groove. wherein said panel-shaped elements (2a, 2b) are manufactured of wood-based material; wherein said panel-shaped elements (2a, 2b) are configured such that they can be coupled to each other at an angle by means of a locking tongue and groove connection and thereby respectively form a connection, an inner corner and outer corner, wherein the inner corner and outer corner define a theoretical miter line; wherein said locking tongue and groove connection respectively is formed of a tongue on one of said panel-shaped elements, of a groove on the other of said panel-shaped elements, and of locking elements (10, 11) provided on said tongue and groove; wherein the panel-shaped elements (2a, 2b) are configured such that they can be coupled to each other laterally and at an angle by means of a turning movement and/or a snap movement to form said connection; wherein, seen in cross-section, the panel surface (6a, 6b) of each of the two panel-shaped elements (2a, 2b) at the side of the formed outer corner in the connection extends at least up to the center line (Mb, Ma) of the panel-shaped element (2b, 2a) to which it is coupled; wherein said locking elements (10, 11) are only present at the height of one side of the tongue; wherein said tongue is cut free on at least one side by means of a narrow incision, wherein by a narrow incision, an incision is meant having a depth which is larger than the width; wherein by cut free is meant freed from still present surrounding material of the respective panel-shaped element; wherein said groove, on at least one side thereof, seen in cross-section, is bordered by a protruding lip extending to beyond said theoretical miter line, seen from the panel-shaped element comprising the groove; wherein said protruding lip is located at the side which is situated closest to the formed outer corner; wherein at the height of this protruding lip at least one contact surface (17, 18) is formed between the tongue and the groove.