250ml (8 fl.oz) wine vinegar
1 clove garlic
2 bay leaves
1 onion, finely chopped
60ml (4 tablesp) tomato puree
90ml (6 tablesp) oil
900g (2 lbs) button or small closed cup mushrooms
1. Put vinegar, garlic, bay leaves and chopped onion into a saucepan. Bring to the boil and simmer until the onion is tender.
2. Add the tomato puree and oil. Mix together thoroughly and season to taste.
3. Pour the marinade over the rinsed mushrooms. Cover and leave to cool.
4. Remove garlic and bay leaves and chill in fridge until required.