Polenta, almond and lemon cake

450gr ground almonds
2 tspns vanilla essence
6 eggs
zest of 4 bio lemons + juice of 1 lemon
225gr polenta flour
1,1/2 tspns baking powder
1/4 tspn salt (which I forgot, so I would say it is optional)

Heat the oven to 180°. Butter flour and fat till pale and light. Stir in ground almonds and vanilla, beat in the eggs, fold in the lemon zest & juice, polenta, baking powder. Grease a cake tine and spoon in the mixture. Bake for about 50 minutes or more, checking and if necessary lowering the heat slightly. The cake should be brown and it remains deliciously softish inside, with a strong taste of lemon.