Method

Preheat oven to 195ºC/175°C fan. Line a deep 24-cm tart tin with the pastry, pressing it into the corners and sides. Remove any excess, overhanging pastry and freeze for at least 10 minutes. Line the pastry case with parchment paper, fill with baking beans and bake on a flat tray for 30 minutes.

Carefully remove the parchment and beans, using any pastry trimmings to plug any holes. Return to the oven for 5 to 10 minutes or until lightly golden. Very lightly brush the tart case with a little beaten egg and return to the oven for 2 minutes.

Melt the butter and a drizzle of oil in a pan over a medium heat and add the leeks, cut sides down, and cook for 3–4 minutes on each side until lightly golden. Season with salt and pepper, turn the heat down low and cover for 5–10 minutes until very tender. Transfer to a plate.

Add the chorizo to the pan and cook until some of the fat releases. Fold in the spinach and cook for 10 minutes until all of the liquid has evaporated, then transfer to a large bowl.

Add the eggs, crème fraîche, cream and chives, and season with lots of black pepper and a little salt. Fold in the manchego cheese. Spoon the mixture into the tart shell and push the leeks into the filling.

Return to the oven for about 30 mins until the custard is just set but still has a tiny wobble in the centre, then let cool for at least 30 minutes before slicing and serving with a fresh green leaf salad.