1Place onions in 3- to 4-quart slow cooker. Add beef. Top with baked beans and barbecue sauce.
2Cover and cook on low heat setting 8 to 10 hours.
3Remove beef from cooker; place on cutting board. Shred beef, using 2 forks. Return beef to cooker and mix well. Stir in chili. To serve, place 1/2 cup beef mixture in each roll and top with 2 tablespoons coleslaw.