This soup is really easy and quick to make and I think it is a subtle combination of flavours – people always seem to sip up every drop so they must think so too. The mild whole seed mustard is much the best for this if you can get it.
Slice the mushrooms very thinly sideways keeping the stalks on so they make a mushroom shape. Melt the butter gently in a fairly large heavy based saucepan. Stir the mushrooms into the butter and cook gently for about a minute or two. Add the cream and the milk, salt, black pepper and the mustard. Heat but do not boil. When it is hot very gradually add the lemon juice, stirring all the time. This will thicken the soup. If you add the lemon juice too quickly it may curdle – you can uncurdle it by straining the liquid from the mushrooms and whizzing it in the blender for a moment or two. (You can uncurdle sauces in this way too.) Taste for seasoning and add extra salt and pepper or mustard if you feel it needs it. Serve the soup with crusty fresh bread, preferably warmed in the oven first.
© 1976 Josceline Dimbleby. All rights reserved.