Cook pasta according to package directions. Meanwhile, in a large skillet over medium heat, melt 1 tbsp butter. Add bread crumbs; cook until browned. Remove from skillet; reserve. In same skillet over medium heat, melt remaining butter. Stir in flour and cook, stirring, for 1 minute. Add milk all at once. Cook and stir until mixture boils. Cook 2 minutes more. Stir in 1 1/2 cups cheese and ham. Add hot pasta to skillet; toss to coat. Top with remaining cheese and buttered crumbs.