Pinterest again! Original recipe here (and if you’re doing P90X, which I’m not, this is a good resource for you!). In the original recipe, she talks about using the baby bellas and making them an appetizer, which would be good, too. But using the big portobellos is less work, in my opinion.
Here’s how I did it (this serves 2, and I didn’t eat all of mine):
4 large portobello mushrooms, stems and gills removed and finely chopped (you can use the part of the stem above the knobby part)
1/4 cup chopped onion
1/4 cup chopped red or green pepper
1 tsp olive oil
pizza sauce (probably around 3/4 cup)
6 oz shredded mozzarella cheese
12 slices of turkey pepperoni (or more if you want)
Preheat oven to 400 degrees.
Saute the chopped mushroom, onion and pepper in a non-stick skillet with the olive oil. Remove from the pan when done, and let it sit on a couple of paper towels to remove excess moisture.
While the vegetables are cooking, put a silicone baking mat on a cookie sheet (or lightly oil the pan to keep the mushrooms from sticking). Lay mushrooms on the sheet, gills-side up, and bake for 10-12 minutes, until softened. If there is liquid in them when you remove them from the oven, dab dry with a paper towel.
Lightly salt the mushrooms, and then add the toppings: first sauce, then vegetables, followed by shredded cheese and pepperoni.
Return to the broiler for 3-4 minutes, until cheese is melted and barely starting to bubble/brown.