Lightly spray a 9x13 inch pan with nonstick spray, and place the bread cubes in it.
In a mixing bowl, combine the milk, cream, pumpkin, brown sugar, eggs, vanilla, and pumpkin pie spice. Pour over the bread cubes. Cover with plastic wrap and place in the refrigerator overnight or at least 3 hours.
When ready to bake, preheat the oven to 350 degrees F.
In a medium bowl, combine all of the streusel ingredients and stir until crumbly. Sprinkle over the bread cubes and then bake for 50 to 60 minutes or until golden brown and set. Sprinkle with powdered sugar and serve topped with warm maple syrup.