Cook noodles according to package directions. Drain. In a large saucepan, melt butter; blend in flour, onion, garlic powder and pepper. Add broth and milk; cook and stir until bubbly and thickened. Stir in 1/2 cup Parmesan cheese. Spread 1/2 cup sauce in the bottom of a greased 13 by 9 inch baking pan. Stir mushrooms into the remaining sauce. Lay 3 noodles in the pan. Top with asparagus, chicken, mozzarella and about 1 cup sauce. Top with 3 more noodles, the cooked ham and half of the remaining sauce. Cover with remaining noodles and sauce. Sprinkle with the remaining Parmesan cheese. Bake, uncovered, at 350° for 35 minutes or until heated through.