Skillet Chicken with Tomatoes

• 4 boneless chicken breast halves
• 1/4 cup chopped onion
• 1/3 cup grated Parmesan cheese
• 1/2 teaspoon rosemary -- crushed
• 3 tablespoons flour
• 1 can (14.5 ounces) diced tomatoes with Italian seasonings
• 1 cup mushrooms -- sliced

Flatten chicken slightly. Coat with 3 to 4 tablespoons of the Parmesan cheese and then coat with flour. Sprinkle with salt and pepper. In skillet cook chicken in oil over medium-high heat until done. Remove to serving dish; keep warm. In same skillet, cook mushrooms, onion, and rosemary until soft. Add tomatoes; cook, uncovered, over medium heat until thickened. Spoon mixture over chicken; sprinkle with remaining Parmesan cheese. Serve chicken with sauce over spaghetti or other pasta.