Chop the vegetables into cubes. Peel and halve one onion, piercing it with the cloves. Chop the second onion and set it aside.
In a big pot bring 6-3/8 cups salted water to a boil. Add the beef, bones, vegetables, the onion, and bay leaf to the water and boil for 90 minutes. Meanwhile, peel and dice the potatoes.
Remove the meat from the broth and set aside. Strain the broth and bring back to a boil. Boil potatoes in the broth until they are cooked.
Prepare the spätzle according to the package. Cube the meat and add both the meat and spätzle to the potatoes in the broth. Add nutmeg to taste.
Melt the butter in a pan and sauté the second chopped onion until golden brown.
Serve the stew with the browned onion and optional parsley.