Cheese and Squash Tart

For the pastry: sift the dry ingredients into a mixing bowl. Rub in the butter until the mixture resembles fine breadcrumbs.

Make a well in the centre and carefully add some of the egg and water mixture - just enough to bring the pastry together. Bring the dough together into a ball. Knead lightly on a surface dusted with flour until smooth.

Wrap in cling film and chill for at least 30 minutes to firm up.

Heat the oven to 200°C (180° fan) 400°F gas 6. Grease a deep 20cm|8" flan dish or tin.

Roll out the pastry about 3mm thick between 2 sheets of non-stick baking paper, to hold the pastry together.

Line the dish with the pastry and prick the base with a fork. Chill for 15 minutes.

Cover with non-stick baking paper and fill with baking beads or baking beans and bake for 10 minutes.

Remove the paper and beans and cook for a further 5 minutes until the base is dry to the touch.

For the filling: grate half the squash into a bowl and slice the other half.

Heat the butter in a pan and cook the onion for 2 minutes, stirring continuously. Increase the heat, add the grated squash and continue to cook for 2-3 minutes, until the slightly softened. Taste and season with salt and pepper. Set aside to cool.

Whisk together the eggs, yolks, mascarpone and cream, then stir in the cheddar and parmesan. Drain any excess liquid from the vegetable mixture, season again to taste, and mix lightly.

Spoon into the pastry case and level with the back of the spoon. Arrange the squash slices on top of the filling and drizzle with olive oil.