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. Th