For the pastry

• 110 g/4 oz plain flour
• 50 g/2

To make the pastry, add the butter to the flour and rub in. Add the egg yolk, the salt and enough water to form a firm dough. Chill for 30 minutes.

Preheat the oven to 350°F/180°C/Gas Mark 4. Roll out the pastry as thinly as possible and use to line a