1 (3 pound) beef brisket, trimmed and cut in half
1 cup ketchup
1 small onion, chopped
1 tablespoon prepared horseradish
1 tablespoon prepared mustard or mustard seed
1 tablespoon honey
1/2 teaspoon pepper
Place the brisket in a 3-qt. slow cooker. In a bowl, combine the remaining ingredients. Pour over brisket. Cover and cook on low for 6 hours or until tender.
Remove the beef; set aside. Pour the sauce into a saucepan; cook, uncovered, over low heat for 13-15 minutes or until reduced and thickened, stirring occasionally. Slice the meat across the grain; serve with sauce.