Preheat the oven to 180oc Grease a non stick loaf tin and then dust with flour to prevent sticking. Cream the butter and sugar together then gradually add in the beaten eggs. Mix until light and fluffy.
Stir in the flour, baking powder and lemon zest and mix well before adding in just two tablespoons of the lemon juice.
Mix until combined then beat in the milk.
Pour into the cake tin and bake for around 45 minutes until a skewer comes out clean.