For the cheese sauce: fry the onion in butter until soft. Add the QimiQ Sauce Base, vegetable stock and cheese and bring to the boil.
Bring salted water to the boil. Push the spaetzle batter through a spaetzle sieve (or allow to drop from a teaspoon) into the boiling water. As soon as the spaetzle rise to the surface, remove with a draining spoon.