1 ¾ cups cake flour
Preheat oven to 350*F. Line a muffin tin with 12 paper liners.
Sift the cake flour, baking powder, baking soda, and salt three times, set aside.
Using a mixer fitted with the paddle attachment, beat the butter on low until it’s softened a bit. Add the sugar and increase the speed to medium. Beat until fluffy, about four minutes. Add one egg at a time, beating well after each addition. Add the lime juice, zest, and food coloring and beat until mixed. (The mixture will look curdled.)
Add the flour in three additions, alternating with the buttermilk, beginning and ending with the flour, scraping down the bowl as necessary. Mix on low until just combined. Fill each cupcake liner 2/3 full.
Bake 20-25 minutes. Cool completely and frost with cream cheese icing.
Makes 12-14 cupcakes.
adapted from Bon Appetit, Sept 2008