To make stuffed mushrooms, remove the stems from white mushrooms, mix cheese, bread crumbs, olive oil, garlic and herbs in a bowl, and place a small amount of filling in the base of each mushroom. Bake the stuffed mushrooms for 25 minutes at 400 degrees Fahrenheit.
Preheat the oven to 400 degrees Fahrenheit, and mix 1/2 cup bread crumbs, 1/2 cup of grated Pecorino Romano cheese, 2 tablespoons of olive oil, two cloves of minced garlic and 2 tablespoons fresh Italian parsley in a bowl. Add salt and pepper to taste, and add 1 tablespoon of fresh mint leaves if desired. Dried parsley and mint can be used in place of fresh herbs. When using dried herbs, reduce the parsley to 2 teaspoons, and reduce the mint to 1/4 tablespoon.
Mix to combine the ingredients, and set the filling aside. Remove the stems from approximately 28 white mushrooms, and clean the mushrooms thoroughly. The mushrooms should measure about 2 1/2 inches in diameter. Place a small amount of the filling in the stem cavity in each mushroom, and place the mushroom on the baking sheet with the filling side up. Bake the mushrooms at 400 degrees Fahrenheit for approximately 25 minutes or until the mushroom is cooked and the filling is hot.