Basic Tomato Sauce

You can use this to enrich and enliven all kinds of sauces, soups and stews. It will keep in the fridge for about 4 days and in the freezer for 1 month. Then use it rather like a stock cube or as a sauce in its own right for pasta, risotto or casseroles. To this basic sauce you can add flaked tuna fish, stoned and chopped olives, mushrooms or anything else which takes your fancy.