- Heat 1 tablespoon of olive oil over medium heat in a medium pan. Add mushrooms and sauté for 3 minutes, stirring once. Add garlic and sauté for 1 minute longer. Cool for 3 minutes.
- Transfer mushrooms to a food processor and pulse 7-8 times to finely chop. Transfer mushrooms to a medium mixing bowl with ground beef, egg, panko, soy sauce, oregano and parsley. Use hands to mix thoroughly.
- Form mixture into 4 large burgers, leaving a well in the center. Heat 1 tablespoon of olive oil over medium-high heat in a non-stick medium pan for 2 minutes. Add 2 burgers and cook for 5-6 minutes on each side. Repeat with remaining burgers. Serve hot topped with your favorite burger fixings.