Preheat your griddle to medium low heat.

Add butter, onions, salt and pepper. Allow them to cook down and deeply caramelize for about 20 minutes, stirring frequently, until the onions become very dark, soft and jammy. If the onions start to burn turn down the heat.

Add in the garlic, thyme, wine or broth, Worcestershire, balsamic, and allow it to bubble up and reduce for about 30 seconds. Remove mixture from the griddle and set aside.

NOTE: the French onions can be made ahead of time. Simply reheat them before assembling your burger.

In a small bowl combine the salt, onion powder, garlic powder, paprika, and pepper. Set aside for later.

Divide the ground beef into 4 patties.

Season patties on both sides with the seasoning mixture.

Add patties to the griddle and cook for 4-5 minutes before flipping and cooking an additional 4-5 minutes.

Add your slices of cheese and allow them to get nice and melty before removing from the griddle.

During the last few minutes add the burger buns to the griddle and allow them to get nice and golden brown. Be careful because the extra butter in the brioche buns cause them to brown quickly.

Assemble your burger with a bottom bun, mayonnaise, burger patty, French onions, and top bun. Enjoy!