In a bowl, beat the flour, eggs, water and salt until the batter starts to bubble. The dough is sliced in boiling water. Bring the resulting spaetzle to the boil briefly and skim it off with a strainer spoon.
In a preheated casserole dish, add layers of spaetzle, grated cheese, salt and pepper to taste.
I don`t mix up the layers. I put the mold in the preheated oven (250 ° C) for about 15 minutes on top heat until the cheese (top layer) is baked golden yellow.
Before serving, put the golden-brown onions and butter over the pasta.