Grandmother's cake - custard and pine nut tart (Torta della nonna)

1. Make the shortcrust pastry as for the crostata: mix the flour with the sugar, baking powder, half the lemon zest and salt, rub in the cold butter, knead quickly with the eggs and chill for 30 minutes.

2. For the custard, bring the milk to the boil with the other half of the lemon zest; in a bowl, whisk the egg yolks with the sugar and starch until smooth, then pour in the hot milk in a thin stream, whisking constantly.

3. Pour back into the pan and cook over medium heat, stirring constantly, until thickened and it bubbles once; pour into a bowl, cover the surface with cling film and let cool.

4. Preheat the oven to 175 °C; roll out a little more than half the pastry and line a buttered 24 cm tin with it, spread in the cooled custard, then cover with a round rolled from the remaining pastry and press the edges together.

5. Scatter the pine nuts on top (pressing them lightly into the pastry) and bake for 40-45 minutes until golden.

6. Let it cool completely in the tin, dust generously with icing sugar and serve in slices.

Tip: A classic of Tuscan trattorias; it needs at least 2 hours to cool before slicing or the custard will run - it keeps for 3 days in the fridge, and you can use flaked almonds instead of pine nuts.