Heat oven to 325 degrees. Place cupcake liners in the two pans in every hole.
In large bowl, add all of the cake ingredients and mix on low speed 30 seconds to combine and then on high for two minutes.
Fill cupcake liners 2/3 full. Bake 20-30 minutes or until center is set. Do not over bake or they will be dry and rubbery. Take out of the oven and cool completely.
To frost; Open two of the cans of frosting. If you bought three cans, leave the lid on that one in case you don't use it. Put the two cans of frosting in a large bowl. Add the lime zest and food coloring until you get a color you like that would reflect the color of a margarita. Mix well to incorporate everything. Spoon the frosting into pastry bag with big round tip and frost the cupcakes.
You could top the cupcake with some extra lime zest for garnish. Little sugar pearls are fun to use as well.