To prepare the “BUNS”…Preheat oven to 350 degrees F. Spray the inside cups of muffin pans with no stick cooking spray. (about 32) Mix a (15.25oz) box of yellow cake mix as directed on box. Spoon about 2 1/2 tablespoons of batter into each cup and bake about 8-10 min or until toothpick comes out clean when inserted in center. Remove to a cooling rack.
To prepare the “Burgers”… Mix a (15.25oz) box of chocolate cake mix as directed on box. Spoon about 1 tablespoon of the mix into muffin pans, sprayed with no stick cooking spray. (about 64) Bake 6-8 minutes or until toothpick comes out clean when inserted in the center. Remove to a cooling rack.
To make the frosting,place the confectioner sugar in a large mixing bowl. Add the shortening and 1/4 cup water. Slowly beat together on the lowest speed of mixer. Add additional water a tablespoon or 2 at a time and increase speed on the mixer. Beat until smooth.
Divide icing into separate small bowls. Using a toothpick or end of a plastic butter knife,add the coloring paste to each bowl. If icing is too thick,add drops of water and stir to desired consistency;if too thin,add small amounts of confectioner sugar.
Divide into 3 bowls, add coloring paste to each (yellow for mustard, green for lettuce, and red for ketchup)
Cut the yellow cupcakes in half horizontally and spread some green icing on bottom half, place chocolate cupcake on top, spread some red and yellow icing on top of this and then top with remaining cupcake top. It looks great when the red and yellow are dripping over the side.
Place each cupcake on a paper cupcake liner, add a little green icing on the top and add a party toothpick to each.