Preheat the oven to 170 degrees
Mix the butter, eggs and sugar with a mixer.
Mix the flour with the baking powder , stir in the egg mixture, add the lemon juice, and stir well. Fill the muffin pans 2/3 full and bake for about 20 minutes.
Leave the cupcakes to cool, if desired, sprinkle with powdered sugar or decorate with icing with lemon juice.
For the glaze -squeeze out the juice of half a lemon , add powdered sugar and stir well with a whisk. if you want the glaze to be thicker, add another tablespoon of powdered sugar.Bon Appetit!