Preheat the oven to 350 degrees.
Arrange potatoes, cabbage, and onions around a large sheet pan. Drizzle on avocado or olive oil and toss to coat. Sprinkle on salt and pepper.
Bake for 15 minutes, remove from oven, and add sausage.
Return to oven and bake an additional 10-15 minutes, until potatoes are slightly crispy and brown.
Serve immediately with a big squirt of spicy brown mustard (my favorite!) and a heaping spoonful of chow chow. SO good.