Modest ingredients add up to a richly flavoured family soup. Creamy butter beans, with a little onion and leek to sharpen them, have their flavour lifted by the smoky taste of the fish. You can use smoked cod instead of the haddock.
Put the stock on to heat in a medium saucepan. Peel and finely chop the onion. Trim the leeks, cut into thin slices and rinse well.
Heat the oil in another saucepan and cook the onion and leeks gently for 5 minutes, stirring occasionally. Add the stock, bring to the boil, reduce the heat, cover and simmer for 5 minutes.
Add the butter beans and their liquid to the pan and mash roughly. Return to the boil, reduce the heat, cover and let simmer.
Skin the haddock and dice the flesh, discarding any bones. Add the fish to the soup and simmer until the haddock is heated through and opaque.
Chop the parsley. Season the soup to taste with the black pepper (the smoked fish should be salty enough without adding extra) and sprinkle over the chopped parsley. Serve, if you like, with a spoonful of cream swirled into each bowl.