01 -
Preheat your oven to 350°F. Spray a baking dish large enough to hold the mushrooms with non-stick cooking spray to prevent sticking.
02 -
Remove the stems from the mushrooms and clean each mushroom cap using a dry paper towel. Avoid using water to prevent sogginess.
03 -
In a mixing bowl, combine all the filling ingredients including clams, green onion, beaten egg, minced garlic, bread crumbs, oregano, and Parmesan cheese. Mix thoroughly to distribute flavors evenly.
04 -
Fill each mushroom cap with 1-2 spoons of the prepared filling. Arrange the stuffed mushroom caps, filling side up, in the prepared baking dish.
05 -
Drizzle 3 tablespoons of melted butter over the stuffed mushrooms. Cover the baking dish tightly with foil and bake in the preheated oven for 20-30 minutes, until the mushrooms are tender.
06 -
Remove the foil from the baking dish. Sprinkle shredded mozzarella cheese over each mushroom. Return the dish to the oven and bake uncovered for 2-3 minutes, or until the cheese is melted and bubbly.
07 -
Remove the baking dish from the oven and serve the stuffed mushrooms warm.