Heat oven to 375°F. Spray 2-quart casserole with nonstick cooking spray. Cook rotini to desired doneness as directed on package. Drain.
Meanwhile, melt butter in large saucepan over medium-high heat. Add shallots; cook and stir 1 minute. Stir in flour; cook 30 seconds. With wire whisk, stir in broth. Add mushrooms. Bring to a boil. Cook 3 to 4 minutes or until thickened, stirring occasionally. Remove from heat; stir in cheese until melted.
Add cooked rotini, chicken, artichoke hearts, tomatoes and parsley to mushroom mixture; mix gently. Spoon into sprayed casserole.
Bake at 375°F. for 25 to 30 minutes or until thoroughly heated and bubbly. If desired, garnish with additional fresh parsley.