01 -
Heat olive oil in a skillet over medium heat. Add sliced onions and cook for 10 to 12 minutes, stirring occasionally, until soft and golden. Add minced garlic and cook for 1 minute until fragrant. Set aside.
02 -
In a large bowl, gently mix ground beef, breadcrumbs, egg, milk, Worcestershire sauce, onion powder, garlic powder, dried thyme, salt, and black pepper until just combined.
03 -
Fold half of the caramelized onions into the meat mixture to infuse the loaf with rich onion flavor.
04 -
Preheat oven to 375°F (190°C). Transfer meat mixture to a loaf pan or shape into a loaf on a parchment-lined baking sheet. Smooth the surface gently.
05 -
Bake for 35 to 40 minutes until the meatloaf firms and cooks through, filling the kitchen with savory aromas.
06 -
Remove from oven. Top with Swiss cheese slices, remaining caramelized onions, and optional shredded mozzarella. Return to oven and bake 8 to 10 minutes until cheese melts completely.
07 -
Let the meatloaf rest for 5 minutes to allow juices to redistribute before slicing and serving.