Speedy Salmon Casserole

1 tablespoon butter or margarine
1 tablespoon all-purpose flour
3 tablespoons ketchup
1/2 cup milk
1 can (14-3/4 ounces) salmon, drained, flaked and bones removed
2 cups mashed potato flakes
1 cup (4 ounces) shredded cheddar cheese

In a saucepan, melt butter over medium heat. Stir in flour and ketchup until smooth. Gradually stir in milk. Bring to a boil; cook and stir for 2 minutes. Add salmon. Prepared mashed potatoes according to package directions.

Spoon half into a greased 11-in. x 7-in. x 2-in. baking dish. Top with salmon mixture, remaining potatoes and cheese. Bake, uncovered, at 375° for 15-20 minutes or until heated through and cheese is melted. Makes 6 servings.