-
For lemon curd, in a heavy saucepan, cook and stir sugar, lemon juice and butter until smooth. Stir a small amount into egg; return all to pan. Bring to a gentle boil, stirring constantly; cook 2 minutes longer. Stir in lemon peel. Cool 10 minutes. Cover and chill for 1 1/2 hours or until thickened.
-
In a mixing bowl, cream butter and sugar. Add eggs, one at a time, beating well after each. Add vanilla and lemon peel. Combine flour, baking powder, baking soda and salt; add to creamed mixture alternately with buttermilk.
-
Fill paper-lined muffin cups three-fourths full. Bake at 350 for 20-25 minutes or until a toothpick comes out clean. Cool 10 minutes; remove from pan to a wire rack. Cool completely.
-
Cut a small hole in the corner of a pastry or plastic bag; insert a small round pastry tip. Fill bag with lemon curd. Insert tip 1 inch into center of each cupcake; fill with curd just until tops of cupcakes begin to creack.
-
Combine frosting ingredients, tinting with food coloring if desired; frost cupcakes. Store in a refrigerator.