1. Grease a 9 x 13 casserole dish with butter.
2. Cut bread into 1 inch chunks and spread evenly in the bottom of the casserole dish.
3. In a large bowl, whisk together the eggs, milk, sugars, vanilla, cinnamon and pumpkin. Pour the mixture evenly over the bread, getting all the bread wet from the mixture.
4. Cover the casserole and store in fridge for several hours or overnight.
5. To make the streusel topping (this can be made ahead and refrigerated), combine the flour, brown sugar, spices and salt. Add the butter and cut into the dry mixture until it all comes together to form a crumble. You can store this mixture in the fridge overnight if you’d like.
6. When you’re ready to bake the casserole, preheat oven to 350 degrees F.
7. Crumble the streusel topping evenly over the top of the casserole, covering as much of it as you can.
8. Bake for 45 minutes for a softer, more moist texture. Bake an hour or more for a firmer, less moist texture.
10. When casserole is ready, serve warm with syrup and other toppings such as powdered sugar, pecans or fresh fruit.