Mushroom Sauce

• 2 oz (50 g) butter
• 1 small onion
• ½

Very small tightly closed mushrooms must be used for this recipe, as mushrooms that are open will discolour the sauce, making it dark.

Melt half the butter in a frying pan over low heat. Peel and finely chop the onion. Add to the pan and fry very gently for about 5 minutes, until the onion is soft but not browned. Meanwhile trim and wash the mushrooms in cold water, then drain and slice