This week I am writing from Rome, where I am celebrating my sister Simona’s 40th birthday. Preparing for a big party is one of my favourite activities and the crostata di ricotta e cioccolato is one of Simona’s favourite desserts.

This tart originates from the old Roman ghetto and is one of a number of dishes that can now be found almost anywhere in Rome and beyond. But should you ever be in Rome, go to the ghetto, where you will find a little pastry shop called Boccione which makes a fantastic torta di ricotta e cioccolato. Its recipe is secret but I have now mastered my own version. If you would like to see me making the tart, then come along to my next class at the Divertimenti cookery school in Marylebone High Street, W1, on June 3, where I will demonstrate this and other Shavuot recipes.

Time: 1 hour 45 minutes

Serves: 8-10

Ingredients
For the pastry:

• 200g plain white flour (ideally ‘00’ type)
• A pinch of salt
• 100g caster sugar
• 100g chilled butter
• 1 egg
• Grated zest of half a lemon
• 500g dry beans to help bake the pastry (not to eat)

For the filling:

• 500g ricotta cheese
• 100g white caster sugar
• 1 egg
• 50g diced dark chocolate or chocolate chips

Method

• First prepare the pastry. Mix the flour in a bowl with the salt and lemon zest, then crumble the butter into the flour with your fingertips.
• Whisk the egg separately with the sugar and then add it to the mixture and work until you form a ball. Wrap it in clingfilm and place in the fridge for at least half an hour.
• TIP: The pastry can be prepared in advance and kept in the refrigerator for up to 48 hours before preparing the tart. It can also be frozen and then defrosted prior to use.
• While the pastry is in the fridge, preheat the oven to 180°C/350°F/Gas Mark 4 and prepare the filling.
• In a bowl, gently beat the egg with the sugar, add the ricotta and mix well. Finally, add three quarter of the diced chocolate and mix thoroughly.
• Take the pastry out of the fridge and remove the clingfilm. Cut it into two uneven parts and wrap up the smaller piece of pastry.
• Roll out the bigger piece with a rolling pin on a floury surface and place in a low round 26cm baking tin. 
• Cover the pastry with greaseproof paper and then add baking beans to cover the whole surface of the tin. Bake for 20 minutes. Remove the paper and beans and bake the base for a further 5 minutes.
• Remove the tart base from the oven and fill it with the ricotta mixture you prepared earlier. Take the remaining pastry, cut it into pieces and roll the pieces into thin strings of different lengths.
• Place each string on top of the tart to form a grid. Brush a little beaten egg on top of each string so it will be glazed and shiny once cooked.
• Finally, grate/add the rest of the chocolate on top to decorate.
• Place the tart in the oven and bake for 40-45 minutes. Wait at least half an hour before removing it from the baking tray. Serve while still warm or at room temperature.