Preheat your oven to 400 degrees F.
Place your sliced onions and sweet peppers onto a lined baking sheet, toss with your olive oil and then sprinkle with 1 tsp of creole seasoning, salt and pepper. Slice your sausage links into 1 inch think pieces and place on top of your onions and peppers. Sprinkle with the remaining 1 tsp of creole seasoning and more salt and pepper.
Bake for 25 minutes, toss and then continue baking until the peppers and onions are soft with a little char on the edges, about 35 minutes.