1. Preheat oven to 450°F. Toss sliced white mushrooms in 1 Tbsp. of the olive oil; set aside.
2. Heat remaining oil and sauté onions until lightly browned, about 5 minutes.
3. Spread sautéed onions over bottom of pizza shell. Layer cheese, beef and reserved mushrooms over onions.
4. Bake at 450°F for about 12 min. until crust browns and cheese melts. Sprinkle with chopped pepper. Cut into 8 slices.
Recipe and photos courtesy of the Mushroom Council and mushroominfo.com. Credit: Pennsylvania Dept. of Agriculture/Eastern Mushroom Marketing Cooperative, Inc.