Flavorful Hearty Slow Cooker French Onion Meatballs Recipe

Ingredients

• 1 lb (450 g) ground beef (or mix of beef and pork)
• 1 large egg
• ½ cup (50 g) breadcrumbs
• ¼ cup (25 g) grated Parmesan cheese
• 1 tsp garlic powder
• 1 tsp onion powder
• ½ tsp salt
• ¼ tsp black pepper
• 2 tbsps chopped parsley (optional)
• 2 large onions, thinly sliced
• 2 tbsps unsalted butter
• 1 tbsp olive oil
• 1 tsp sugar
• 1 tsp garlic, minced
• 2 cups (480 ml) beef broth
• 1 tbsp Worcestershire sauce
• 1 tbsp cornstarch mixed with 2 tbsps water (slurry)
• ½ tsp thyme (optional)
• ¼ cup (60 g) shredded Gruyere or Swiss cheese (for topping, optional)