2 large lemons
220g/15 tablespoons salted butter, soft
220g/1 cup plus 2 tablespoons (Caster) sugar
4 eggs, lightly beaten
190g/11/3 cups ground almonds
125g/1 cup polenta/cornmeal
11/2 teaspoons baking powder
18cm/7inch round cake pan, base lined with baking parchment
Preheat the oven to 170C (325F) gas 3
Grate the zest from both lemons, and squeeze the juice from just one.
In a large bowl, cream the butter and sugar together until pale and fluffy. Add the eggs one at a time, beating between each addition, then stir in the lemon juice and zest, followed by the ground almonds, polenta/cornmeal and baking powder.
Spoon the mixture into the prepared cake pan, sooth level with a palette knife and bake in the preheated oven for 80-90 minutes. A skewer inserted in the middle should come out clean. Remove from the oven and allow to stand for a while. When cool enough to handle, run a knife around the inside of the pan and turn out onto a wire rack to cool completely.
The cake will keep for 4-5 days in an airtight container.