Cut all of the vegetables and sausage into bite-sized pieces and spread out in a single layer on a large, foil-lined sheet pan. Drizzle olive oil over the whole pan. Add oregano, parsley, garlic powder, salt and pepper. Toss until evenly coated.
Bake in a 400 degree oven for 25-30 minutes, stirring half way through.
Remove from oven and top with parmesan cheese if desired.