In A Large Skillet, Saute The Chicken In Oil Until Lightly Browned; Sprinkle With The Lemon-Pepper. Add The Frozen Vegetables, Tomatoes, Onion, Basil And Onion Powder. Bring To A Boil. Reduce Heat; Cover And Simmer For 6-8 Minutes Or Until Chicken Juices Run Clear And Vegetables Are Tender Meanwhile, Cook Pasta According To Package Directions; Drain. Top With Chicken Mixture. Serve With Parmesan Cheese If Desired.