Tart Crust

1. Prepare a 22cm/8.6 inch tart tin
2. Place flour, sugar, salt and butter in the bowl and rub between your fingertips until the dough resembles sands
3. Add the yolk and knead until a smooth dough
4. If too wet add a little more flour, if too dry add a splash of milk (or put all the ingredients in a food processor and blitz until it forms a dough)
5. Roll the tart dough out into a circle slightly larger than your tart tin
6. Line the tart tin with the pastry and trim the edges
7. Dock the base of the pastry with a fork and place in the fridge to chill for 1-2 hours
8. Preheat the oven to 180C
9. Place a piece of baking paper in the unbaked tart shell and fill with baking beans or uncooked rice
10. Blind bake the tart pastry for 30 minutes, then remove the baking beans and baking paper and bake for another 10-15 minutes, or until golden brown (if the edges are getting too dark, cover them with aluminium foil)

Cream Cheese Filling

1. Combine the cream cheese, ricotta/mascarpone, parmesan, milk and butter in a large heatproof bowl
2. Melt the cheeses over a double boiler, mix until smooth
3. Add the eggs, vanilla, cornstarch and sugar, and continue stirring the mixture for 10 minutes or until thickened
4. Remove from heat and cover with cling wrap. Chill in the fridge for at least 1 hour until chilled.

Assembly

1. Preheat the grill to 240C/465F
2. Fill the baked tart shell with the cream cheese filling and smooth off the top
3. Lightly brush the top with the beaten egg yolk
4. Bake the cheese tart for 10 minutes, or until lightly golden
5. Use a fine-meshed sieve to sprinkle over the icing sugar on top of the tart
6. Using a blow torch, torch the top of the tart until it is burnished
7. Place in the freezer to set for 1 hour
8. Remove, slice and bring to room temperature
9. Serve!