Creamy Noodle Beef Casserole

1 jar dried beef, 5-ounce
4 cups noodles, cooked
1 can cream of mushroom soup, 10 3/4-ounce
1/3 cup milk
1/4 cup grated cheese
2 tablespoons finely chopped onion
1/2 cup soft breadcrumbs
1 tablespoon butter or margarine
Heat oven to 350 degrees. Rinse dried beef with boiling water; drain. Chop dried beef into small pieces. Combine beef, noodles, soup, and milk; mix well. Stir in cheese and onion. Spoon this mixture into 1-1/2-quart casserole. Toss together breadcrumbs and butter; sprinkle over beef mixture. Bake 30 minutes or until hot.