A roux is a cooked butter and flour mixture and the first stage in the preparation of a white sauce. Preparing a roux can be the most time consuming part of making a sauce. But you can save time by making a roux mix in advance and storing it in the refrigerator. The mix keeps for several months and has plenty of uses.
Melt 8 oz (225g) butter in a large saucepan. Stir in 8 oz (225g) plain flour and blend well. Cook very gently for about 15 minutes, stirring frequently. As the roux cooks it will become lighter in colour and sandy in texture. Draw off the heat and allow to cool. The mixture sets quite hard. I like to break it up with a wooden spoon and press it through a coarse sieve or grate the lumps so the mix maintains a crumbly texture for easy measuring. Tip into a polythene bag and store in the refrigerator.
To use: For every 1/2 pint (300ml) heated milk add 2 rounded tablespoons roux mix off the heat and stir to blend. When the mix has blended in the milk, return the pan to the heat and bring to the boil, stirring all the time to make a smooth sauce. Simmer gently for 2-3 minutes to thicken. Season with salt and pepper and it’s ready to use. If your sauce is not thick enough, add more mix and if it’s too thick, add more liquid.