Five years ago I would have NEVER eaten anything like this ... so never say never!
Note: If I have a very thick mushroom, I will cut off the top and level it off. It certainly is user's taste preference.
I first found this recipe on allrecipes.com for the burger and then realized the taste was very conducive for making a pizza out of the same recipe.
I no longer measure and mix all the ingredients in the recipe. I just spray on the extra virgin olive oil, I use Fustini's https://www.fustinis.com/ Garlic Infused olive oil (purchased on-line) and I brush on Giuseppe's http://giuseppesoils.com/18-Year Balsamic (purchased at Partridge Creek Mall in Clinton Township, MI or now in Grosse Pointe), and shake on organic garlic powder, organic oregano, and organic basil.
Note: Fustini's and Giuseppe's source their oils and vinegars from the same provider.
When making the pizza, I use Organic Valley's cheese from grass-fed cows (Whole Foods), Wellshire Farm's uncured pepperoni (Whole Foods), and Rao's Homemade (Whole Foods) pizza sauce.
Here is the link for the original recipe . . . http://allrecipes.com/recipe/14497/portobello-mushroom-burgers/?internalSource=search%20result&referringContentType=search%20results