My microwave is notorious for being gross! It seems like every time I open the door there is more crap shellacked to the top and sides. It took me awhile to find a method that didn’t involve a ton of time and scrubbing. This is the best method that I have tried.
You take one cup of white vinegar and one cup of water and let it run in the microwave for ten minutes. While you wait all the gross cooked on stuff is being steam cleaned and softened. I ran the rough side of a sponge over everything and I was done.
Very easy and no nasty fumes!