In a large saucepan, saute garlic in butter for 1 minute. Stir in the flour, salt and pepper until blended. Gradually add milk. Bring to a boil; cook and stir for 2 minutes or until thickened and bubbly. Stir in mustard and Colby cheese; cook and stir until cheese is melted. Add pasta and ham; stir until coated.
Transfer to a greased 2-qt. baking dish. Sprinkle with Parmesan cheese. Bake, uncovered, at 350° for 20-25 minutes or until heated through.