Pastry shell-
Place the flour into a mixing bowl, add the salt, cut up the butter into small pieces , stir through the butter and rub in with cool fingertips. Stir in the egg yolks and a little cold water to bring it into a pliable dough. .
Shape into a flattened disc and wrap in clingfilm and rest in the fridge for 30 minutes.
Roll out the pastry on a floured surface, the crust should be no more than 6mm/¼-inch thick and then used to line a flan tin which, in general, are no deeper than 4cm/1½-inches. Trim away excess pastry, line with a sheet of foil and baking beans. Chill for 30 minutes.
Bake blind for 15-20 minutes in a preheated oven at gas 6/200c/400f, remove from the oven, and remove the foil and beans. Reduce the temperature of the oven to gas4/180C/160C Fan for about 10-15 minutes until dry to the touch. Now you are ready to fill and bake your tart.
The filling-
Brush the cooked pastry shell interior with the mustard.
Top with the cooked leeks.
Heat the milk in a pan, add the grated cheese, mustard and chilli powder and melt the cheese slowly over a low heat. Remove from the heat and stir in the flour. Mix well and return to the heat and thicken, stirring all the time. Remove from the heat and cool a little, then whisk in the eggs. Pour over the top of the leeks, top with a good crust of cheese and breadcrumbs and bake at 200c/180c Circotherm/gas 6 until bubbling and golden on top.
Pastry Case
250g plain flour
¼ teaspoon sea salt
140g chilled butter
2 egg yolks
3-4 tablespoons chilled water
Rarebit filling
Rarebit filling
1 teaspoon Dijon mustard for the tart base
3 Medium leeks, trimmed, washed and finely shredded sautéed in 50g butter
150ml full fat milk
1 teaspoon mustard powder
1/4 teaspoon chilli powder
30g plain flour
200g full flavoured hard cheese
3 medium sized eggs
Topping
50g full flavoured hard cheese mixed with 2 tablespoons of breadcrumbs and 1 tablespoons chopped herbs.