Au Gratin Potatoes

1/4 cup margarine
1/4 cup flour
1/2 teaspoon salt
2 cups milk
1 cup (4 ozs.) cheddar cheese
1/2 cup parmesan cheese
5 cups (5 medium) peeled, sliced raw potatoes
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1/4 cup dry bread crumbs
1 tablespoon margarine or butter, melted
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- Heat oven to 350 degrees F. In medium saucepan, melt margarine, stir in flour and salt. Add milk; cook until mixture boils and thickens, stirring constantly. Stir in cheeses and potatoes. Pour into 2-quart casserole or individual casserole dishes.
- Combine crumbs with melted margarine; sprinkle over potatoes.
- Bake covered at 350 degrees F. for 1 to 1 1/2 hours, or until bubbly. If desired, garnish with chopped chives