More elaborate than a simple bake, but the results are worth and very satisfying.
Melt the butter over a moderate heat. Add the sliced leek and cook for 4-5 minutes, stirring occasionally. Leek should be translucent.
Stir in the flour and cook for a further minute. Pour in the milk, stirring continuously, and cook until it boils.
Remove from heat, season, and mix in the grated cheese.
Beat the two egg yolks and blend in a little of the hot sauce, then pour this mixture back into the leek and sauce pan. Stir to mix well. Cool.
Preheat the oven to 400° F (200° C).
Line one 8-inch pie pan with pastry.
Pour in the cooled leek sauce.
Bake on the middle rack for 25-35 minutes, until the crust and the top are golden brown.
For a gluten free recipe use a gluten free pie crust or bake the filling in a pie dish with no crust.
For a more satisfying pie, get enough pastry to line the pan top and bottom and, after pouring the leek sauce, roll out the rest of the pastry and cover the pie. Make a cut on the top to let the steam out. Bake until the top crust is golden brown.
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