Stuffed pancakes

This is an awful faff to make, but worth it once in awhile.  Serves 4.

For the pancakes:
110 g buckwheat flour (or gram flour, or even plain wheat flour)
1 egg
250 ml milk
Seasoning

For the stuffing:
1 tbs oil
1 onion
1 clove garlic
1/2 punnet mushrooms
2 large tomatoes
1 slice bread
30 g (approx) walnuts
Seasoning

For the béchamel sauce:
25 g butter
250 ml milk
2 heaped tsp flour
2 large handfuls grated cheese
Seasoning

First make the pancake batter by whisking together the egg, flour and milk, seasoning as liked.  Leave to stand while you make the stuffing: peel and chop the vegetables (probably no need to peel the mushrooms), cook in the oil until soft and juices run; whizz bread and nuts in a food processor until smooth, and then mix into the rest of the stuffing.

Make your pancakes in the usual way - this amount makes about 4 large ones.  It's probably easiest to layer them up with stuffing in between, but I tried to be clever and roll them round the stuffing:

 Melt the butter in a clean saucepan, and whisk together the flour, milk and seasonings.  Pour this on to the melted butter and bring to the boil, stirring all the time.  Remove from the heat and stir in half the cheese.  Pour this mix over the pancakes, and then top with the rest of the grated cheese.

You can easily make this vegan; the stuffing already is.  For the pancakes, use water or beer instead of milk, and a tablespoon of olive oil or tahini instead of the egg.  For the sauce, use a tin of tomatoes instead of the milk, and season more vigorously to make up for the lack of cheese.