Peel the asparagus, cook with the peel, a piece of margarine or butter, sugar, salt and a piece of lemon peel in the water until al dente. When done, remove the asparagus from the water and place aside on a plate. Remove the peel and reduce the stock, possibly after seasoning. Melt the butter or margarine in a saucepan, sprinkle in the flour, toast it lightly and then pour the asparagus stock over it, always stirring well. Add the cream and sprinkle with the grated cheese. Spice up .