In a medium non stick skillet, over medium heat, melt butter until bubbling. Add the mushrooms and cook for 2 minutes if fresh, if jarred, add the spinach now too and cook until wilted.
Add the tomato and saute until most liquid is gone.
Now add the eggs, salt and pepper too. Swirl your eggs with a spatula until halfway done, then add the avocado and cheese, continue cooking until eggs are no longer runny, but you don't want them too dry. I always remove when still nice and wet, but not slimey as they will continue to cook some..
Serve with your favorite breakfast bread and a few slices of avocado in the side.