Black Olive Tart Slice

For the pastry: sift the flour into a mixing bowl and stir in the salt. Rub in the butter until the mixture resembles breadcrumbs. Gradually add the egg yolk and water, a tablespoon at a time, mixing continuously until the mixture just comes together as a dough. (You may not need to use all of the water). Roll the dough into a ball, then wrap in cling film and chill for 1 hour.

Heat the oven to 180°C (160° fan) 350°F gas 4. Grease a 20 cm|8" pie tin or dish.

Roll out 2/3 of the dough on a floured work surface, until it is almost twice as wide as the diameter of the pie tin. Line the base and sides of the tin. Gently press the pastry into the corners of the tin, trimming off any excess, then prick the base of the pastry case several times with a fork.

Cover the pastry with a sheet of non-stick baking paper and fill it with rice or dried beans. Bake for 10-15 minutes, until the pastry is pale golden. Remove from the oven, discard the beans and paper and set aside to cool.

Arrange the mozzarella and tomatoes on the base. Scatter over the garlic, some salt and ground black pepper and the olives. Drizzle with olive oil.

Roll out the remaining dough on a floured surface until it is slightly larger than the diameter of the pie tin. Brush the rim of the cooked pastry case with some of the beaten egg and place the pastry lid on top of the pie. Trim off any excess pastry. Seal the pastry lid to the pastry case by crimping the edges of the pastry lid with a fork.