Mix the flour, eggs, a little fizzy drink, salt, pepper and nutmeg to make a smooth dough. Put the spaetzle dough in a spaetzle press and cook in boiling salted water until it floats on top. Stir with a wooden spoon to prevent the sparrows from sticking together. When the sparrows swim to the surface, remove them with a slotted spoon and drain well.
Chop or grate the cheese and mix together, then spread over the spaetzle in layers. Bake in the oven at 180 ° C until the cheese has melted or the desired brown color has been achieved.
In the meantime, cut the onions into fine strips and fry them slowly in a pan with butter until they are really crispy brown. Spread these on the finished cheese sparrows.