Remove the stem from the mushroom caps. Place mushroom caps in a baking dish. Combine garlic powder, baking blend, 1/4 cup shredded cheese, mayo and crab meat. Spoon into mushrooms caps. Sprinkle with remaining cheese, parsley and Old Bay Seasoning. Bake at 375 degrees F. for 12-15 minutes. Cut into quarters before serving. Serves 10.