Serves 4-6

2 cups skim milk
1 onion, cut in half
1 small carrot, roughly chopped
1 stalk celery, roughly chopped
6 peppercorns
2 tbsp plain flour

1. Pour the milk into a saucepan.  Add the chopped vegetables and peppercorns.  Bring mixture to the boil.  Immediately reduce heat and simmer for 15 minutes. 
2. Strain the milk into a bowl.  Discard the vegetables and peppercorns.  In a separate bowl, mix the flour with 2-3 tbsp of the warm milk.  Stir to form a smooth paste.  Gradually add the rest of the milk, stirring all the time. 
3. Return the sauce to the saucepan.  Bring to the boil, stirring constantly.  Reduce heat and simmer gently for 2 minutes, stirring until the sauce thickens.

Microwave method:
Cooking time:  approximately 7 minutes

Blend to a smooth paste the flour and ¼ cup of the milk and set aside.  In a casserole, blend the remainder of the milk with all the other ingredients.  Cover with plastic wrap, microwave on ‘High’ for 1-1½ minutes, stirring once during cooking.