To make the pastry: With your fingers rub the butter lightly into the flour, until it resembles breadcrumbs. Add a pinch of salt along with enough cold water to make a smooth dough. Mix well then wrap the dough in cling film and rest in the fridge for 20 minutes.
To cook the pastry: After the pastry has rested take it from the fridge. Roll out the pastry thinly. Line a loose-bottom quiche tin - 3cm deep x 23cm. Be careful to press the dough firmly into the edges of the tin. Let the pastry rest for another 10-15 minutes.
Pre-heat the oven to Gas Mark 5, 190°C. Put a baking sheet in the oven to heat up. Line the pastry with cling film, tin foil or parchment paper. Then fill with rice, dried beans or metal or ceramic baking weights. This stops the pastry base rising during cooking. Place on the baking sheet in the oven and bake for 15 minutes.
Remove the pastry case from the oven and remove the cling film and rice, dried beans or baking weights. Brush the pastry with a little beaten egg (from the filling ingredients) and cook for a further 5 minutes or until golden.
To prepare the filling: Meanwhile, melt the butter in a frying pan over a medium heat. Add the leeks and cook for 3-4 minutes until soft, remove to a plate and let cool. Add the broccoli to a pan of boiling water. Bring back to the boil and simmer for a minute, drain, then run cold water over the broccoli to cool it quickly.
Next, add the cream and milk to the beaten eggs along with the grated cheese, the leeks and spinach, season and mix well. Gently add the mixture to the pastry case then add in the broccoli florets.
Place the tin on the baking sheet in the oven and cook for 35-40 minutes - the filling should feel firm be golden brown and puffy.
Serving Suggestions
Let the quiche sit for a couple of minutes before taking it from the tin and placing it on a serving plate or board. Serve cut into wedges.