Preheat the oven to 400°. Place a piece of parchment paper on a baking sheet and set aside.
Brush the outside of the mushrooms with a little olive oil and arrange on baking sheet.
In a large bowl combine crab meat, 1/3 cup Panko crumbs, parmesan, mayonnaise, cream cheese, green onions, celery, herbs, salt and pepper.
Stuff each mushroom cap generously with the crab mixture.
Combine oil and remaining Panko crumbs until evenly coated. Sprinkle the panko mixture over the tops of the mushrooms.
Bake until the mushrooms begin to brown, approximately 15 minutes then broil for 2 minutes until golden all over with crispy tops.
Choose mushrooms about the size of a half dollar.