In the Dude's Cheeseburger, which item is included in the toppings?

In the Dude's Cheeseburger, red onions are included in the toppings. Red onions add a distinctive sharpness and a slightly sweet flavor that complements the juicy beef patty and enhances the overall taste of the burger. They also contribute to the visual appeal with their vibrant color. The other toppings listed, such as avocados, bell peppers, and mushrooms, are not standard toppings for this specific burger. Each of those items brings unique flavors and textures, but in the context of the Dude's Cheeseburger, red onions are specifically chosen to elevate the dish in alignment with its intended flavor profile.