The butter mix with sugar until white. Add egg yolks one at a time, the grated rind of lemon, baking powder, flour and beaten egg whites. All stir and pour into cake form, greased with butter and sprinkled with flour. Bake in a moderate oven. Once the cake is baked and cool, pricked and pour the hot syrup, which is prepared as follows: sugar, lemon juice, grated lemon rind and the butter boil 5 minutes. The cake is cut into the next day to be watered well.