Step 1

For the baby cakes: Preheat oven to 350° F. A couple notes: I prefer to use flexible silicone mini muffin pans with no paper liners for this recipe, but you can also prepare metal mini muffin pans with paper liners. I use these silicone muffin pans, which yield a little bigger mini cupcake than most - which I like! Sizes of mini muffin pans vary quite a bit, so your yield and baking time may vary. I set the silicone muffin pans on sheet pans, for sturdiness.

Step 2

In a medium bowl, whisk flour, baking powder, and salt. Set aside.

Step 3

In a large bowl, beat butter until smooth. Add sugar and beat to blend. Beat in eggs one at a time, then the lime juice, lime peel, and food coloring. Batter may look curdled, but that's just fine. Beat in the flour mixture alternately with the buttermilk, in 3 additions. Spoon batter into liners, about 2/3 full.

Step 4

Bake cupcakes until tester inserted into center comes out clean. This takes about 20 minutes for me, but it will depend on the size of your tins, so pay close attention to your baking time. Cool 10 minutes and remove from pan. Cool completely before adding frosting.

Step 5

For the frosting: In a medium bowl, beat all ingredients until smooth. With a medium-large plain round pastry tip (I like to use one that has a tip opening of about 5/16"), pipe frosting onto cooled cupcakes, or simply spread it on with a knife. Sprinkle a bit of fresh lime zest over tops, if desired.