Preheat oven to 350 degrees
Prepare the crisp topping by combining in a medium bowl crushed ginger snap cookies, oats , flour , brown sugar , cinnamon , baking powder and salt.
Dice cold butter and cut it into the dry mixture either with a pastry cutter or 2 knives
Set this mixture aside
In a large bowl combine canned pumpkin, slightly beaten egg and milk. Mix with a wire whisk until combined well.
Mix in both sugars, pumpkin spice and vanilla extracts.
Pour pumpkin filling into a sprayed 9x13 baking dish
Evenly spread the crisp mixture over the pumpkin
Bake in a preheated oven for 40-45 minutes or until golden brown
Serve warm with vanilla ice cream or whipped cream