Method

• 1.
  Grease a 1.5-litre (6-cup) capacity souffle dish with melted butter. Evenly sprinkle the parmesan around the base and side, then refrigerate for 15 minutes to chill.
• 2.
  Place the milk, bay leaves and onion in a saucepan and bring to the boil. Turn off heat and leave for 15 minutes to infuse.
• 3.
  Meanwhile, in a separate pan, melt the butter over low heat and add the flour. Cook, stirring, for 2-3 minutes to make a roux. Strain the milk mixture into the roux and cook over low heat for 1-2 minutes, stirring until thickened. Add the nutmeg and cayenne pepper and season well with salt and freshly ground black pepper. Remove from the heat and stir in the egg yolks, then add the cheese and beat until well combined. Place mixture in a large bowl, cover with plastic wrap and set aside.
• 4.
  Preheat oven to 190°C.
• 5.
  Beat together the egg whites and cream of tartar in a bowl until stiff. Beat 4 tablespoons of the egg whites into the cheese mixture to loosen. Carefully fold through remaining egg whites (trying not to lose too much volume). Transfer to the chilled dish and bake in the oven for 15 minutes. Reduce oven temperature to 170°C and cook in the oven for a further 15 minutes. Serve immediately.