Preheat the oven to 350 degrees F. Line cupcake pan with paper liners.

In electric food mixer, cream the butter until soft. Add the sugar and lemon zest, and beat until the mixture is light and fluffy. Beat in eggs one at a time, then sift in the flour, and baking powder, and fold into the butter mixture. Alternatively, you can whiz or pulse all the ingredients together in an electric food mixer .

Divide the mixture evenly among the paper liners, and bake in the preheated oven, until the cupcakes have risen and are golden, about 15 minutes. When cooked, the center of each cake should be slightly springy to the touch. Remove the cakes from the pan, and place on a wire rack to cool completely before icing.