Clean the asparagus, hard to break off the tip; cut into 3 centimeters slices. Boil water with sugar, salt and a little piece of butter, reduce heat, and cook the asparagus to lower the lid for 20 minutes. Fold the asparagus in a colander, save the broth. Put the asparagus back into the pot, add milk and cook 10 minutes. Fold the asparagus in a colander, to preserve milk. Melt the butter and fry it until a cream-colored flour mixture gradually pour in the broth and milk, broccoli, interfere with, to avoid lumps. Cook for 5 minutes, add salt and pepper. Beat the egg yolk with the cream, put in the soup to warm up, but do not boil. Return the asparagus to the soup and serve.