Pre-heat the oven to 175C (380F) fan-forced and grease and line a 20cm round cake tin.

In the bowl of an electric mixer, beat the butter, zest and sugar together until light and creamy.

Add the egg and mix it through.

Beat through half the flour then half the milk and repeat then beat until the batter is smooth.

Scrape the batter into the tin and bake for 30-35 minutes or until a cake tester comes out clean.

Transfer to a wire rack straight from the oven but leave it in the tin.

Meanwhile make the syrup.

Place the lemon juice and sugar in a small saucepan and heat, stirring, over medium heat until the sugar has dissolved and the mixture bubbles.

Poke holes all over the top of the cake and pour the syrup on top.

Leave in the tin to cool.