Preheat oven to 425°F. Line a large sheet pan with foil.
Toss sausage and vegetables with oil, garlic, Italian seasoning, salt, and pepper. Spread evenly on sheet pan.
Roast for 20-25 minutes, flipping halfway through, until sausage is browned and vegetables are caramelized.
While the pan roasts, cook penne according to package directions. Drain and set aside.
Toss roasted sausage and vegetables with hot pasta on sheet pan or in a large bowl. Add a splash of pasta water if needed.
Serve topped with Parmesan.