Introduction: How to Make a Macchiato. A  macchiato is a beautiful, and tasty scientific drink.It consists of layers of Chocolate, foam, milk, and coffee. And with the right tools and proper techniques, they are very easy to make.I have separated this instructables into several steps. Grinding Tamping and Pouring, Foaming, and Layering. Each step needs proper techniques and practice  to do it successfully.For this you will need:Espresso MachineEspresso CupsCoffee BeansCoffee GrinderThermometer MilkChocolate Sauce TamperCold Milk Frothing Pitcher Glass CupHere's the finished product Step 1: Grinding, Tamping, Pouring.. Grinding:Ideally you would grind your coffee with a bur grinder, but those can be very expensive, and most people don't have access to one so I will teach you how to use a blade grinder.Coffee is freshest immediately after it is ground.  After grinding coffee beans, the oils that were protected inside the bean are exposed to the air which oxidizes and stales the coffee.  This occurs immediately after coffee grinding so it is important to tamp and extract the espresso as quickly as possible.  The coffee grinder should be ran for 15-20 seconds every time a shot is desired so that only freshly ground coffee is used, for this reason it is not recommended to use pre-ground.Tamping:When your tamping the goal is to make a pellet of coffee that the the hot water from the espresso machine will penetrate evenly.  Since the water from the espresso machine is under pressure, the espresso pellet must be hard and evenly tamped. Once your done grinding, put the ground coffee into you filter,  use 2.5 to 3 teaspoons for a double shot. Put the filled coffee filter on a sturdy surface, and take your coffee tamper and place it on top of the coffee in the filter. It should fit snugly into the top of the filter. If the tamper is too small, the coffee around the edges of the filter won_x0019_t be compressed, and the water will flow through the grounds there, losing its flavor. Press straight down, applying even, firm pressure. You should aim for about 30 pounds of pressure. Push down, twisting slightly in one direction and lift straight up. The surface of the coffee should be smooth with no crumbs. Brush away any crumbs of coffee from around the edge of the filter and place the filter onto your espresso machine.Pouring:As a general _x0018_rule of thumb_x0019_, the darker the roast the shorter the extraction time should be. For example, espresso uses a Dark roast, and therefore the extraction time is quite short. The ideal rate-of-pour for espresso has the consistency of syrup, About  25-30 seconds.To preserve the flavor of your coffee beans, you must protect them from moisture, light, and above all, air Step 2: Foaming. When foaming your milk, use very cold milk.  It is important to keep the milk temperature right above freezing.  Keep the steam pitchers in the refrigerator also.  This will allow you to steam the milk for a longer period of time. Fill your milk pitcher half way with cold milk and place the tip of the frothing wand  about 1/4 inch_x001D_- 1/2 inch_x001D_  below the milk surface level. Then slightly tilt the pitcher (if the bottom of the pitcher is parallel with the floor, tilt  the pitcher about 15 degrees).  Make sure to tilt the front of the pitcher towards the frothing device. Then release the valve to full blast. You will will hear a high pitched squeal, as this happens you will notice the level of the milk will rise. If you see large bubbles starting to grow on the top of the milk, your wand is too close to the top, and if you see no foam form on the milks surface, and hear a deep, throaty wine, the wand is down too deep.Keep doing this until a foam dome is formed at the very top of the pitcher. Once the temperature reaches 180 degrees, stop heating the milk.This can take a lot of practice to get it just right, so I recommend using an electric milk frother until you master it. Step 3: Making the Layers. Once you have your espresso shots, and frothed milk, take out your glass cup and chocolate syrup.The first thing you pour in is your milk, on the bottom will be your milk, and on top will be the foam.Then pour in your espresso shots right down the middle, you will notice it stays in the middle.Then take out your chocolate syrup and pour it in until you can see it at the button, and then put a thin layer of chocolate on top of the foam. (make sure not to make it too thick or it will sink.)And you have your finished product, a 5 layer macchiato.This is a great example of density.  Looking at this drink we can see that Chocolate Sauce is very dense, and the foam is not.Density is a measure of how much mass is contained in a given unit volume (density = mass/volume). Put simply, if mass is a measure of how much ‘stuff’ there is in an object, density is a measure of how tightly that ‘stuff’ is packed together.