Brown Chicken Stock

Very easy to make. Brown chicken bones in a little oil in a hot oven. Transfer to a large saucepan and fill with water 3 inches above the bones. Bring to the boil. Skim the surface and immediately lower the heat to simmer. Add chopped carrot, onion, celery, a teaspoon of tomato purée, thyme, parsley, bay and black peppercorns. Simmer for 4 hours topping up with water if necessary. Strain and reduce by half.