Ham and Green Noodle Bake

This has been one of my favorites for years and years!  It is not easy to find spinach or green noodles anymore.  I have also used plain fettuccine and it works as well.

1 medium onion chopped
2 T butter
2 T flour
1/2 tsp. salt
1/4 tsp. pepper
1/4 tsp. dry mustard
1 3/4 C. milk
2 cups cubed ham
1/2 C. shredded Swiss cheese
4 oz. spinach noodles
2 T grated Parmesan cheese

Heat oven to 375. Cook and stir onion in butter until tender.  Blend in flour, salt, pepper and mustard.  Heat over low heat, stirring constantly until bubbly.  Remove from heat.  Add milk, heat to boiling stirring constantly.  Boil and stir 1 minute.  Stir in ham and Swiss cheese.

Cook noodles as directed on package.  Drain.  Alternate layers of noodles and sauce mixture in ungreased 1 1/2 quart casserole dish.  Sprinkle with Parmesan cheese.  Bake uncovered until bubbly and light brown.  About 20 minutes.