100g/3½oz very cold butter, cut into small cubes, plus extra for greasing
60g/2¼oz ground almonds
60g/2¼oz icing sugar, sifted
½ lemon, zest only
1 large free-range egg yolk
1 tsp vanilla extract
For the filling
300g/10½oz ricotta cheese
100ml/3½fl oz cream
½ lemon, zest only
3 tbsp lemon juice
5 tbsp runny honey
6 large free-range eggs, separated
150g/5½oz pine nuts
icing sugar, for dusting
200g/7oz crème fraîche
To make the pastry, rub the butter into the flour until the mixture looks like breadcrumbs. Mix in the ground almonds, icing sugar, lemon zest and salt.
Make a well in the centre and incorporate 3 tablespoons of ice-cold water a little at a time, kneeding gently. Just as the dough starts to come together, mix in the egg yolk and vanilla extract.
Turn the mixture out onto a clean work surface and knead lightly until it forms a ball. Press into a flat circle, wrap in cling film and refrigerate for 30 minutes.
Preheat the oven to 180C/160C Fan/Gas 4. Grease a 20cm/8in pie or tart tin, roughly 4cm/1½in deep, and dust with flour.
Dust a clean work surface with flour and roll out the dough into a circle about 5mm/¼in thick. Press the pastry into the tin, concentrating on the sides. Trim off most of the excess pastry, leaving some around the edge to allow for shrinking. Refrigerate for 10-15 minutes.
Prick the pastry base with a fork, line with greaseproof paper and pour in the baking beans. Bake for 15 minutes, remove the greaseproof paper and beans and cook for a further 5 minutes until lightly golden. Trim any excess pastry and set aside on a wire cooling rack.
Meanwhile, make the filling. In a large mixing bowl, beat together the ricotta, mascarpone, cream, lemonjuice and zest, honey and egg yolks until smooth.
In a separate bowl, whisk the egg whites until stiff peaks form. Fold the egg whites into the ricotta mixture one spoonful at a time.
Pour the mixture into the pastry case and sprinkle over the pine nuts. Cook for 30–35 minutes, or until slightly set at the sides but still wobbly in the middle. Cool on a wire rack for at least one hour.
Dust with icing sugar and serve in generous slices with a dollop of crème fraîche.