Preheat the oven to 180C/Gas 4. Grease an ovenproof roasting dish (or disposable like I do at Christmas time!) with some butter.

Boil the sprouts in salted boiling water for about 3-4 minutes, drain and put in the greased dish. Add the chesnuts

Fry the bacon pieces until crisp.

Make the sauce by mixing together the crème fraîche, mustard and milk.

Pour over the sauce and sprinkle with the cheese and cooked bacon.

Bake for 15-20 minutes until bubbly and golden.

Can be made in advance and cooked when needed.

Turn this dish vegetarian by omitting the bacon.