Preheat the broiler. Line a sheet pan with foil and coat the foil with cooking spray.
Place the ground beef, eggs, breadcrumbs, onion, salt, pepper and garlic powder in a large bowl. Stir until thoroughly combined.
Shape the meat mixture into 1 inch meatballs and place the meatballs on the prepared pan.
Broil for 8-10 minutes or until golden brown.
While the meatballs are cooking, prepare the sauce.
Melt the grape jelly by microwaving it for 30 second increments or melting it in a saucepan over medium heat.
After the jelly has melted, whisk in the chili sauce.
Coat a slow cooker with cooking spray. Add the meatballs, then pour the sauce over the top. Toss to coat.
Cook for 3 hours on low. Sprinkle with parsley, then serve.