Heat the oven to 180C/160C fan/gas 4. Tip the flour, 1/4 tsp salt and the butter into a food processor and pulse to fine breadcrumbs. Add the egg yolks and 2 tbsp ice-cold water and pulse again until the mixture clumps, adding up to 2 tbsp more water if needed. Tip onto a lightly floured surface and bring together into a disc with your hands, then wrap tightly and chill for 30 mins.

Roll the chilled pastry out on a lightly floured surface into a 30cm round. Use it to line a 22cm fluted tart tin, leaving any excess overhanging the rim, then chill for 30 mins more. Line the pastry case with baking parchment and baking beans and bake for 15 mins. Remove the beans and parchment and bake for 10 mins more. Leave to cool, then trim away any excess pastry using a serrated knife.

Heat a large frying pan over a medium heat and fry the chorizo for 5 mins until beginning to crisp up. Remove to a bowl with a slotted spoon and set aside. Fry the leeks in the residual chorizo oil with a pinch of salt for 10-15 mins until softened, adding a pinch of paprika in the last minute. Remove from the heat and leave to cool for 15 mins.

Whisk the eggs, cream, most of the cheese and chives and some seasoning together. Spread the leek mixture into the base of the tart case, then gently pour over the egg mixture. Scatter with the remaining cheese, chives and paprika. Bake in the centre of the oven for 15-20 mins, then remove and leave to cool for 15 mins before serving with a green salad.