Mushroom Swiss Burger If you're a mushroom lover, this one's for you. Our Mushroom Swiss Burger starts with a fresh, never-frozen seasoned beef patty grilled to juicy perfection, then topped with melted Swiss cheese, savory sautéed mushrooms, and grilled onions. Finished with crisp lettuce and our signature SuperBurger Sauce on a buttery toasted brioche bun, every bite is rich, creamy, and packed with bold, earthy flavor. A hearty classic that's comfort food at its finest. 🍄🧀🍔