Brush dirt from mushrooms with a damp cloth or brush, and pop out the stems. Scoop membranes out with a small spoon.
Use a pastry brush to lightly brush the outsides of the mushroom caps with olive oil.
Bake for 10 minutes. Mushrooms should be tender, but still firm. Pour any pooled juices out of the center of the mushrooms.
Remove mushrooms from oven and change setting to broil.
Stack about 5 spinach or basil leaves, roll them, and cut into thin strips. Repeat with remaining spinach leaves.
Spoon pizza sauce into the mushroom caps. (The amount will vary based on the size of the mushroom.)
Top pizza sauce with spinach leaves and mozzarella cheese.
Return mushrooms to the oven and broil for about 2 minutes or until cheese is melted.
Notes
See step-by-step pictures, serving ideas, and more above.Top tip:For best results, do not clean the mushrooms under running water. Mushrooms absorb water very easily, and the final stuffed mushroom turns out soggy.Low-carb options:Use tomato-based sauce with no added sugar to keep the recipe South Beach Phase 1 compliant.Storage:Store leftover mushroom pizza bites in an airtight container in the refrigerator for about 3 days. To reheat in the oven, cover with foil to prevent them from drying out, and cook for about 10-15 minutes in a 350°F oven.Other topping ideas:Tomatoes, onion, peppers, pepperoni, ham, sausage, black olives, and pineapple—just about any topping you enjoy on a traditional pizza works. The key is to finely dice the ingredients.