Preheat the oven to 180°C.
Grease a 20-22cm round cake tin and line the base with parchment.
Cream butter and sugar together until light and fluffy.
Beat in eggs one at a time until fully incorporated.
Fold in the flour, ground almonds, and lemon zest.
Transfer the batter to the tin and tap to remove air bubbles.
Bake for 35-40 minutes until golden and a skewer comes out clean.
Make 15 holes in the hot cake with a chopstick.
Drizzle lemon juice over the hot cake and allow to cool.
Mix lemon juice into icing sugar to create a smooth paste.
Spread icing over the cooled cake and serve.