Preparation / Directions:
Heat oven to 375 degrees. Prepare potatoes as directed. Cut into enough thin slices to measure about 4 cups. Heat margarine in 2-quart saucepan over medium heat. Cook onion in margarine about 2 minutes, stirring occasionally. Stir in flour, salt and pepper. Cook, stirring constantly, until bubbly; remove from heat. Stir in milk and 1-1/2 cups of the cheese. Heat to boiling, stirring constantly. Boil and stir 1 minute.Spread potatoes in ungreased 1-1/2-quart casserole. Pour cheese sauce over potatoes. Bake uncovered 1 hour. Mix remaining cheese and the bread crumbs. Sprinkle over potatoes; sprinkle with paprika. Bake 15 to 20 minutes longer or until top is brown and bubbly.