Preheat oven to 350°. In a medium bowl, combine 1 1/2 cups graham cracker crumbs, gingersnap crumbs, melted butter, and maple syrup. Coat a 9×11-inch baking pan with cooking spray. Place mixture into the bottom of the pan and press to form a crust. Bake for 10 minutes. Remove from oven and set aside.
In a medium bowl, combine pumpkin purée, evaporated milk, cinnamon, nutmeg, cloves, brown sugar, and egg. Whisk until thoroughly combined. Pour pumpkin mixture over crust and spread evenly. Bake for 40 minutes.
Meanwhile, make the streusel topping by combining walnuts, 1/3 cup graham cracker crumbs, 1/4 cup brown sugar, cinnamon, and butter. Blend with a fork or pastry cutter until the mixture resembles coarse meal.
After pumpkin bars have baked, sprinkle with streusel and bake for an additional 15–20 minutes until golden.
Amount Per Serving
% Daily Value*
Total Carbohydrates 26g9%
Dietary Fiber 1g4%
* Percent Daily Values are based on a 2000 calorie diet.