Meanwhile melt 4 tablespoons of butter, add 4 tablespoons of flour, 1 teaspoon salt and a good pinch of dry mustard. Cook over low heat until bubbly.

Then add 1 1/2 cups milk, cook until thick and smooth. Add 1/2 cup Velveeta processed cheese grated or diced. Stir until all is melted.

Add the beans, pour into a buttered casserole, sprinkle with grated Parmesan cheese and paprika. Bake at 350 degrees for 30 minutes.