Preheat oven to 350 degrees. Spray a large baking dish with cooking spray.
Layer sweet potatoes, apples and onions in the dish. Drizzle with 1 ½ tablespoons olive oil. Sprinkle with rosemary, sage, thyme, salt and pepper. Toss to coat.
Place chicken sausage links on top of the vegetables. Drizzle with remaining olive oil and season with additional salt and pepper.
Place in the oven for approximately 50-60 minutes (flipping the chicken sausage and tossing the veggies and apple slices once half-way through cooking), or until chicken sausage is cooked through and sweet potatoes are soft.
