Creating Cheesy French Onion Meatballs is straightforward if you follow these simple steps:

1. Preheat Oven: Preheat your oven to 375°F (190°C) and line a baking sheet with parchment paper.
2. Sauté Onions: In a skillet over medium heat, sauté the chopped onions in a little oil until they are caramelized and golden brown, about 10 minutes. Add the minced garlic and sauté for another minute. Remove from heat and let cool.
3. Mix Ingredients: In a large bowl, combine the ground beef, breadcrumbs, grated Parmesan cheese, cooled onions and garlic, egg, Worcestershire sauce, salt, pepper, and dried thyme. Mix until everything is well combined.
4. Form Meatballs: Using your hands, shape the mixture into meatballs, about 1 to 1.5 inches in diameter, and place them on the prepared baking sheet.
5. Bake Meatballs: Bake in the preheated oven for 20-25 minutes or until the meatballs are cooked through and browned.
6. Add Broth: Remove the meatballs from the oven and carefully pour beef broth over them to keep them moist.
7. Top with Cheese: Sprinkle shredded Gruyère cheese on top of each meatball, then return to the oven for an additional 5-7 minutes, or until the cheese is melted and bubbly.
8. Garnish: Remove from the oven and garnish with fresh parsley if desired.

These steps will guide you in creating these incredible Cheesy French Onion Meatballs effortlessly.