Split 6 portobello mushroom caps to make 12 thin rounds. Toss 1 1/4 cups shredded muenster cheese, 1/3 cup breadcrumbs, 2 tablespoons chopped parsley, 1 grated garlic clove, and salt and pepper. Layer the portobello rounds and cheese mixture in a baking dish, making 3 layers of each. Drizzle with 3 tablespoons water, cover with foil and bake at 400 degrees F, 35 minutes. Uncover and bake 8 more minutes.