Heat 60 g of the butter in a large pan and sweat the onion and artichokes, with the lid on, over a low heat for 8–10 minutes, stirring frequently. Do not Het them brown. Add the stock or water and season with salt, pepper and nutmeg. Bring to the boil and simmer for 20–25 minutes until the vegetables are soft. Blend the soup, stir in the cream and reheat gently Whisk in the remaining butter and serve at once, garnished with the horns of plenty.