Preheat oven 350ºF/180ºC.
Remove stem and gills from the mushrooms and bake for 20 minutes.
While the mushrooms bake, mix together the ground beef, salt, dried chili and coriander and mold into 4 patties.
Cook the patties for approximately 2 minutes on each side over a medium high heat. While the patties are in the pan, put a slice of cheese on each patty.
In a different pan, sauté the onions until translucent and season lightly with salt and pepper.
Once the mushrooms are done, you can assemble the burgers: mushroom, lettuce, tomato, burger and lastly, onions.