Grease a souffle dish well and preheat a baking sheet in the oven at 190C/375F/Gas 5.
Melt the butter in a pan, add the flour to make a roux, then add milk gradually.
Allow to cool. Beat in the yolks and cheese until smooth.
Chop 25g/1oz of the prawns very finely and add to the sauce, also add half the brandy. Season quite highly with salt, pepper, cayenne and nutmeg.
Fold the mixture into the stiffly-beaten whites.
sauté the remaining prawns in clarified butter for 1 minute, add the remaining brandy and set alight.
Place half the souffli mixture in the dish, place flamed prawns on top, and cover with the remaining mixture.
Place in the preheated oven and bake 40 minutes.