2 lbs ground beef (80/20)
2 large onions, sliced
1 cup shredded Gruyère or mozzarella cheese
1 cup bread crumbs
2 eggs
½ cup beef broth (plus more for onions)
2 tbsp Worcestershire sauce
½ cup ketchup
1 tbsp brown sugar
2 tbsp butter
1 tbsp olive oil
Salt & pepper to taste
Caramelize onions in butter and olive oil, 25–30 minutes. Deglaze with broth.
Mix ground beef, bread crumbs, eggs, Worcestershire, broth, and half the onions.
Shape half into a loaf, fill with cheese, top with remaining beef.
Glaze with ketchup, Worcestershire, and brown sugar.
Bake at 375°F for 50–60 minutes.
Top with reserved onions before serving.
Swap cheese for mozzarella or Swiss if needed.
Rest loaf before slicing for best texture.