For the dough, mix the flour with eggs, lard, water and salt to form a thick dough: Make sure there are no lumps in the dough. Let the dough stand and rest for a while.
Dice the onion and roast it in the remaining lard until golden brown, but do not let it get too dark. Grate the cheese.
For the spaetzle, put a pot of water on to boil. As soon as the water boils, add the salt and, with the help of a spätzle slicer (or a spätzle press), plane the spätzle directly into the water. Lift the finished spaetzle out of the water with a slotted spoon.
Add the drained spaetzle to the onions in the pan and fry them for a while. Sprinkle the grated cheese on top and season everything with pepper (and possibly salt). Serve the cheese spaetzle immediately, sprinkle with chopped chives and enjoy.