01 -
Add the frozen meatballs, chili sauce, and grape jelly to a 5-quart or larger slow cooker. Give everything a good stir to ensure the meatballs are well coated with the sauce mixture.
02 -
Cover and let it cook until the meatballs are thoroughly heated and the sauce has thickened slightly. Choose either 2 to 2½ hours on HIGH or 3 to 4 hours on LOW. For a thicker sauce, remove the lid during the final 30 minutes and crank up to HIGH if needed, stirring occasionally.
03 -
Keep warm in the slow cooker for serving, or transfer to a serving dish. Sprinkle with fresh parsley if desired.