Ricotta and chocolate tart

Combine the flour, sugar and peel and add 80g butter. Using your fingers work the butter into the flour until it resembles breadcrumbs. Beat the egg yolks, lemon juice and 50ml of the water, and add to the flour. Mix to combine and knead on a floured surface. Roll into a circle and fit in the tin. Chill overnight. Lightly grease a 23cm springform tin. Preheat the oven to 200°C. Bake blind for 20 minutes. Reduce the oven to 180°C.

Pass the ricotta through a sieve and beat in the cream, egg yolks, 125ml sugar, liqueur and vanilla extract. Stir in the peel, pour the filling into the case and scatter with the chocolate.

Beat the egg whites until fluffy. Gradually beat in the remaining sugar and beat until it is glossy and smooth. Spoon into a piping bag and pipe zigzag stripes over the filling. Sprinkle with the nuts and cover the rim with foil. Bake for 20 minutes. Cover the whole cake with foil and bake for 20 minutes.

Remove and cool. Chill for 1 hour before bringing it to room temperature and serving.