1. Bake a dozen regular vanilla cupcakes and a dozen mini chocolate cupcakes (just fill the cup with about a third of the batter you normally would.)
2. When cupcakes are cooled, carefully remove the paper cups and cut the vanilla cupcakes ("buns") in half width-wise.
3. Place the chocolate mini cupcakes ("patty") upside-down on top of the bottom half of the vanilla cupcake.
4. Make and colour green, red and yellow fondant. Roll out and cut the green fondant as "lettuce leaves" and place on top of the "patty." Shape and drape the red and yellow fondant on top for ketchup and mustard.
5. Place the top half of the vanilla cupcake on top and sprinkle with sugar.