Cook pasta according to package directions, omitting salt and fat.
While pasta cooks, heat oil in a large nonstick skillet over medium-high heat. Add asparagus, mushrooms, bell pepper, and onion; sauté 4 minutes. Add garlic; sauté 1 minute. Add artichokes and sherry. Cook, stirring frequently, 3 minutes or until most of liquid evaporates. Stir in basil, 1/4 teaspoon salt, and 1/4 teaspoon black pepper. .
Combine 1/2 cup milk and flour; whisk until smooth. Combine flour mixture, 2 cups milk, and butter in a medium saucepan. Cook over medium heat, whisking constantly, 20 minutes or until thick and bubbly. Stir in Parmesan cheese, 1/4 teaspoon salt, and 1/8 teaspoon black pepper.
Preheat oven to 350°.
Combine pasta, vegetables, and white sauce. Spoon into a 13 x 9-inch baking dish coated with cooking spray. Cover and bake at 350° for 30 minutes. Uncover, sprinkle with cheese blend, and bake 7 minutes or until cheese melts.