Grease eight ceramic ramekins and preheat oven to 350°F or 180°C.
Melt the butter in a heavy-base saucepan, then stir in the cornstarch.
Cook for a couple of minutes, stirring constantly.
Pour in the milk and stir well, then add the egg yolks and bring to a boil over medium heat, stirring continuously with a whisk until thickened.
Remove from the heat and mix in the cheeses and seasoning with a spoon.
Return to the heat and stir until the cheese has dissolved.
Set aside and keep warm.
Beat the egg whites with a dash of salt until stiff peaks form.
Gently fold the egg whites into the cheese mixture evenly mixed.
Spoon into the ramekins and bake for 35 - 45 minutes until golden brown and risen.