Heat oven to 400°F. Lightly grease 2-quart casserole.
Cook macaroni according to package directions; drain.
In casserole, stir together SPAM® Classic and macaroni.
In medium saucepan, melt 1 tablespoon butter. Blend in flour, salt, mustard, black pepper and cayenne until smooth. Stir in milk; cook over medium heat, stirring, until mixture thickens and boils. Add cheese; cook, stirring, until cheese is melted. Pour over SPAM® mixture; mix well.
In microwave-safe bowl, melt remaining 1 tablespoon butter; stir in breadcrumbs and paprika. Sprinkle over macaroni. Bake 20 to 25 minutes.