1
Prepare the ground beef by mixing it with some cheddar and mozzarella cheese.
2
Caramelize the onions by cutting them into thin strips and cooking them with honey, salt, and pepper.
3
Make the garlic sauce by mixing Greek yogurt with garlic, salt, pepper, and parsley.
4
Prepare the garlic-Parmesan butter by melting butter, adding garlic, Parmesan cheese, and parsley, and heating it briefly.
5
Assemble the burgers by placing the bottom bun halves in a baking dish, spreading garlic sauce on them, adding the ground beef, caramelized onions, six slices of cheddar cheese, and mozzarella cheese, and topping with the top bun halves.
6
Brush the garlic-Parmesan butter on the top bun halves.
7
Bake the burgers in a preheated oven at 180°C for 15 minutes, or until the cheese is melted and the buns are golden brown.