Wash the mushrooms with a damp cloth and remove their stems, leaving the caps intact.
Finely chop the stems.
Heat the butter in a skillet over medium-high heat and sauté the shallot, chopped mushroom stems and garlic for 3-4 minutes, until soft.
Add the breadcrumbs and Parmesan and cook for another minute.
Stuff the mixture back into the mushroom caps, sprinkle with extra Parmesan and bake on a baking sheet for 15 minutes, or until the mushrooms are tender and golden on top.
