Cook linguine according the package directions. Drain. Keep warm. Melt butter in med. Saucepan. Saute onion until tender. Blend in flour and salt. Gradually stir in E. Milk and water. Cook and stir over med. Heat until mixture comes to a boil and thickens. Remove from heat. Add cheeses; stir until melted. Sliver ham. Add ham and broccoli to pan; heat through. Add linguine; toss to combine. Makes 4 servings.