Cut potatoes in >1 centimeter cubes, boil in water (add 1/4 tsp. salt) that barely covers the top, and cook for ~15 minutes or until the potatoes are to a consistency you like. Add squares of Ham and Cheese and pur over with white sauce. Cook in a casserole dish, or a bread pan works as well at 350 for 15-20 minutes.
Make the white sauce by melting the butter (my mom typically does this in a frying pan) stirring in the flour and then adding in the milk. Stir regularly until it thickens to a state slightly more liquid than gravy. Add salt and pepper. More (or less) salt may be needed depending on the saltiness of your ham and cheese.
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