To start making this easy pound cake, beat the sugar with the butter until you get a smooth, pale cream. You can use an electric mixer if you like.

Separate the egg yolks from the whites. Add the yolks to the butter and sugar mixture one at a time, making sure each yolk is fully incorporated before adding the next.

In a separate bowl, beat the egg whites until stiff peaks form. Add a pinch of salt to help achieve a firm texture. Once ready, gently fold the egg whites into the batter along with the lemon zest, using slow, folding motions. The egg whites are the secret to a light and fluffy cake.

Sift the flour together with the baking powder. Gradually add the flour mixture and milk to the batter, alternating between the two. Continue mixing slowly to avoid lumps.

Grease a baking pan with a little butter and pour in the batter. Bake in a preheated oven at 350°F (180°C) for 40 minutes. Do not open the oven during baking.