Add frozen meatballs to crockpot. Add chili sauce and grape jelly. Cover and cook for 2 to 3 hours on HIGH or 4 to 6 hours on LOW, until the sauce is hot. Serve directly from the crockpot with a serving spoon or toothpicks, or transfer to a serving dish.
Add meatballs to saucepan. Add chili sauce and grape jelly. Cover and simmer over medium heat until the sauce is hot, about 10 minutes.
