-
1
Prepare Cupcakes: Preheat oven to 350u00b0F. Beat 1 cup softened butter at medium speed with a heavy-duty stand mixer until creamy; gradually add granulated sugar, beating until light and fluffy. Add eggs, 1 at a time, beating just until blended after each addition.
-
2
Stir together flour, baking powder, baking soda, and salt. Add flour mixture to butter mixture alternately with sour cream, beginning and ending with flour mixture. Beat at low speed just until blended after each addition. Stir in 1 tablespoon zest, 1 tablespoon juice, and 1 teaspoon vanilla. Place 30 paper baking cups in three 12-cup standard-size muffin pans; spoon 1/4 cup batter into each baking cup.
-
3
Bake in preheated oven until a wooden pick inserted in centers comes out clean, 20 to 23 minutes. Remove from pans to wire racks, and cool completely, about 20 minutes.
-
4
Prepare Frosting: Beat 8 ounces softened butter and lemon zest at medium speed until creamy, 1 to 2 minutes. Gradually add powdered sugar alternately with 8 tablespoons lime juice, beating at low speed until blended after each addition. Add up to 1 tablespoon lime juice, 1 teaspoon at a time, beating until desired consistency is reached. Add food coloring, and beat at high speed until well blended and frosting is light and fluffy, 1 to 2 minutes.
-
5
Spoon frosting into a ziplock plastic freezer bag. Snip 1 corner of bag to make a small hole. Pipe about 1 1/2 tablespoons frosting onto each cupcake.
