Begin by heating olive oil in a skillet over medium heat. Add thinly sliced onions and cook them slowly for 20-25 minutes, stirring occasionally until they turn golden brown and develop a sweet aroma.

In a large mixing bowl, combine the ground beef, breadcrumbs, shredded cheese, egg, garlic powder, thyme, and the cooled caramelized onions. Gently mix until all ingredients are well incorporated without overworking the meat.

Transfer the meat mixture onto a lined baking sheet or into a loaf pan to form your desired shape. Make sure it’s evenly shaped to ensure even cooking throughout.

Preheat your oven to 375°F (190°C) and place your shaped meatloaf inside once heated. Bake for about 50-60 minutes until cooked through, ensuring that it reaches an internal temperature of 160°F (71°C).

After removing the meatloaf from the oven, let it rest for 5-10 minutes before slicing. This resting period allows juices to redistribute, ensuring each slice is moist and flavorful.