1) Combine together the cornstarch and 1 tablespoon of the milk in a bowl and blend to make a smooth paste.
2) Boil the remaining milk and pour it all over the cornstarch. Stir well.
3) Put the sauce back in the pan and add the sugar along with the brandy. Gently cook over low heat for about 2 to 3 minutes.
4) The sauce can be served hot with steamed fruit pudding, Christmas pudding or mince pies.