Stock and Soup: Building Flavour

A good stock needs very little attention, only time and a low heat. It is the difference between a soup that tastes of something and one that does not.

What goes in

Bones give body: the gelatine in them is what makes a cold stock set to a wobble. Chicken wings and carcasses, beef and veal knuckles, and fish frames from white fish are best.

Onion, carrot, celery, leek tops, parsley stalks, a bay leaf and peppercorns give the background flavour. Keep a bag in the freezer for trimmings and bones, and make stock when it is full.

Leave out cabbage and other brassicas, which taste sulphurous after long cooking, beetroot, which colours everything, and starchy potatoes, which cloud it.

Roasting the bones and vegetables first gives a brown stock with deep flavour and colour, for gravies and beef dishes. Unroasted, it is a pale stock, for soups, risottos and lighter sauces.

Keeping it clear

Start with cold water, bring it up slowly, and skim off the grey scum as it rises.

Never let a stock boil hard. Boiling churns the fat into the liquid and leaves it cloudy and greasy; a bare simmer, with only an occasional bubble breaking, keeps it clear.

Chicken stock wants 2 to 3 hours, beef longer, vegetable about 45 minutes, and fish only 20 to 30, after which the bones turn it bitter.

Salt and keeping

Do not salt stock. You will reduce it in sauces and season the finished dish instead.

Chill it and the fat sets on top and lifts off in one piece. It keeps for 4 days in the fridge and 3 months in the freezer; freeze some in ice-cube trays for gravies and pan sauces, or reduce it hard first to save space.

Giving soup depth

Soften the onions slowly, 10 minutes or more, before adding anything else. Their sweetness is the base of nearly every soup.

Something savoury lifts a soup that tastes thin: a Parmesan rind simmered in it, a spoonful of miso, a dash of soy or Worcestershire sauce, or a little tomato purée cooked in with the onions.

Finish with something fresh: a squeeze of lemon, chopped herbs, a swirl of good oil or yoghurt.