Mushroom Ketchup

• 2lb/1 kg field mushrooms
• 3 oz/75

Trim the base of each mushroom stalk and break the mushrooms into small pieces. Arrange in layers with salt in a bowl. Cover with a cloth and leave in a cool place for 5 days, stirring once or twice a day. Cover the bowl with a piece of foil and put into the oven at 300°F/150°C/Gas Mark 2 for 1½ hours. Strain through a jelly bag and leave to drip for an hour until all the liquid has dripped thr