Meatballs can be baked in advance; cool completely. Place in freezer-weight resealable plastic bag; seal bag. Freeze up to 3 months. Thaw in refrigerator before placing in the slow cooker and cooking with sauce as directed.
For less heat, use only half the jalapeño pepper.
For added zing, prepare using KRAFT Sweet & Spicy Chipotle Barbecue Sauce.