French Onion Soup Ingredients Soup • 5 cups sliced onions • 1 tablespoon butter • 2 tablespoons avocado oil • 1 tablespoon salt • 1 tablespoon black pepper • 3 garlic cloves, chopped • 1 tablespoon buttery garlic & herb seasoning • 1 teaspoon garlic powder • 1 tablespoon dried thyme • 1 tablespoon onion powder • 2–3 bay leaves • 5 cups beef broth • 1 teaspoon soy sauce • ¼ cup red cooking wine • 1 tablespoon beef Better Than Bouillon Cornstarch Slurry • 1 tablespoon cornstarch • 2–3 tablespoons