Boil the macaroni in plenty of salted water, cut the spring onion into strips and cut the mushrooms into leaves. Heat the butter, fry the mushrooms all around, add the spring onions and roast everything briefly, add the herbs, salt, pepper (if necessary sprinkle some flour over it and let it sweat). Stir in the water and cream, bring to the boil and melt the cheese in the sauce while stirring. Drain the pasta, drain it well and arrange on plates with the sauce.