Preheat oven to 400 degrees.
Scrape out the gills from the portobello mushrooms, toss or drizzle with the olive oil, and sprinkle lightly with salt and pepper.
Then, lay portobellos on a baking pan open side up.
Scoop ¼ cup of sauce into each portobello cap.
Mix the two cheeses together in a bowl and sprinkle generously (about ¾ cup) into each portobello.
Top each pizza with 5 pieces of pepperoni.
Bake in the oven for 15-20 minutes until the mushrooms are soft and the cheese is bubbly and golden brown.
Garnish with extra Parmesan and sliced basil.
Yield: 4