From Anne's Food
1 medium size cauliflower
100 g cheese, grated (preferrably a rather sharp one)
50 g Parmesan cheese, grated
40 g butter
3 tbsp all-purpose flour
500 ml milk
1 tsp mustard
2 tbsp crème fraiche
salt and pepper
Divide the cauliflower into florets and boil in salted water until they're just beginning to go soft - about 4 minutes. Drain and place in an oven-proof dish.
Make the sauce: Melt the butter in a saucepan. Add the flour and whisk into a smooth paste. Gradually add the milk, but whisk the whole time to make sure you don't get any lumps.
When all the milk is added, turn up the heat and bring to a boil. Lower the heat again and let the sauce simmer for about 5 minutes, until thickened. Add half the cheese and all of the parmesan, as well as mustard and crème fraîche. Season with salt and pepper.
Pour the cheese sauce over the cauliflower, and top with the remaining grated cheese. Bake at 200°C for about 20 minutes. Watch closely towards the end, so it doesn't burn.