2 tbsp. butter
2 tbsp. flour
1 tsp. dry mustard
2/3 c. milk and a little more
2 c. shredded sharp Cheddar cheese
4 c. cooked, cubed potatoes
1 1/2 c. chopped ham (Hormel can - 5 1/2 oz. works great)
1/4 c. green onion slices (or sm. can of fried onions)

Melt butter in saucepan over low heat. Blend in flour and mustard. Gradually add milk; cook, stirring constantly until thickened. Add 1 cup cheese, stir until melted. Stir in potatoes, meat and onion (or 1/4 to 1/2 can). Spoon into 2 quart casserole dish. Bake at 350 degrees for 30 minutes. Top with remaining cheese; continue until cheese is melted.