Slice your onion into thin strips and set aside. Then core and slice your cabbage into thin strips.
Melt your butter in a deep skillet over a medium heat. Add onions and cook until caramelized, about ten minutes. Season with salt, pepper, and garlic powder.
Then add your cabbage slices. It might look like they’re overflowing, but you can cover the pan for a minute or two and they’ll cook down pretty quickly. Then mix the onion and cabbage continuing to sauté.
Add chicken broth and stir.
During this last few minutes of cooking, add your sliced fully-cooked knockwurst to the skillet and stir.
Once the cabbage and onion mixture is completely cooked down and browned on all the edges, about 15 minutes, turn the flame off.
Garnish with parsley and serve warm right from the skillet.