Preheat oven to 350 degrees and grease a 9x9 or 11x7 pan (in the video, I used a deep dish 9x9 dish).
Mix donut holes and bread together, spreading them evenly in the baking dish.
In a bowl, whisk eggs, half and half, pumpkin puree, vanilla extract, pumpkin pie spice and allspice together. Pour the mixture evenly over the donuts and bread.
Allow to sit for 20 minutes so the bread and donuts can soak up some of the liquid (you can make this the night before and let it soak overnight; however, it will be much more custard-like in the center. Because the donuts are naturally softer, it truly only needs about 20 minutes to soak).
Mix brown sugar and flour together. Add the butter to the mixture. Using a fork or a pastry cutter, work the butter into the mixture until it has come together and resembles coarse crumbs.
Sprinkle the topping over the casserole.
Bake for about 30-35 minutes, or until the topping is golden brown and the casserole feels ‘set’ in the center when the baking dish is gently moved.
Allow to cool for a few minutes before serving.
Top with maple syrup or powdered sugar.
Enjoy!