Wash the asparagus and cut off the woody ends. Season water with salt and sugar, bring to the boil. Cook the asparagus for about twelve minutes. In the meantime heat up 1/4 litre of water. Stir in the contents of the bag with a whisk, bring to the boil.
Beat butter over low heat until it melts. Place the asparagus in an ovenproof dish. Pour sauce over it. Sprinkle with cheese and bake in a preheated oven (electric: 225 ° C/ gas: level 4) for about 5 minutes.
Wash herbs. Pluck the chervil leaves from the stems. Serve the asparagus garnished with chervil leaves, dill flowers and lemon. Serve with fresh baquette.