1. Preheat oven to 400 degrees F (200 degrees C). Lightly grease a medium baking dish.
2. Bring a large pot of lightly salted water to a boil. Place fusilli pasta in the pot, cook for 8 to 10 minutes, until al dente, and drain.
3. Heat the oil in a skillet over medium heat. Place chicken in the skillet, and season with minced onion, salt and pepper, garlic powder, basil, and parsley. Cook until chicken juices run clear. Mix in the cooked pasta, cream of chicken soup, cream of mushroom soup, and mixed vegetables. Transfer to the prepared baking dish.
4. In a small bowl, mix the bread crumbs, Parmesan cheese, and butter. Spread evenly over the casserole.
5. Bake 30 minutes in the preheated oven until bubbly and lightly browned.