Before you start, carefully peel a lemon and place the skin to one side, and squeeze the juice in to a bowl. Cream together the butter and sugar in a large mixing bowl.
Beat in the two eggs and add the lemon juice.
Mix in the flour and baking powder. Take a grater and grate the lemon zest in to the mixture. Add the milk and mix together.
Place cupcake cases on a tray and fill each case with 2 tbsp of cupcake mixture. Bake in an oven set at 350"C for 25 minutes.<br/><br/>When cooled. Mix up some glace icing with a few drops of lemon juice, cover the cupcakes and add a jelly lemon.