Ingredients
30g/1oz butter, plus extra for buttering soufflé dish
30g/1oz plain flour ('00' if possible)
150ml/5fl oz full-fat milk
1 tsp Dijon mustard
pinch cayenne pepper
4 eggs, 4 whites and 2 yolks
85g/3oz grated cheese (I use gruyère, but you can use any hard cheese)
salt and pepper

Method
1. Preheat the oven on to 200C/400F/Gas 6.
2. Heat the milk until just below boiling.
3. Melt the butter, stir in the flour and cook for 1 minute. Take off the heat and gradually beat in the milk. Cook for 1 minute until you have a thick sauce.
4. Season well and stir in the mustard. Cool for 1 minute whilst you butter the soufflé dish.
5. Separate the eggs. Beat the yolks into the sauce along with most of cheese.
6. Whisk the egg whites until you have soft peaks, don't overdo. Fold into the sauce. Fill the dish three quarters full. Run your finger round the edge to get a 'top-hat' finish.
7. Place into an oven dish, top with the remaining cheese and a pinch of cayenne.
8. Place in the oven and cook for 15-17 minutes.