In a skillet on the stovetop, brown the ground beef with onion and garlic until no pink remains. Drain any fat.
Place beef mixture in a 4 qt slow cooker. Add ketchup, chili sauce, bell pepper, celery, brown sugar, tomato paste, mustard, vinegar, Worcestershire, and chili powder and stir to combine.
Cook on low 6-7 hours or high 3-4 hours.
Serve over rolls or slider buns.
