Preheat oven to 350F. Line an 8-by-8-inch baking pan with parchment paper, pinch the sides down with medium size binding clips, spray with cooking spray, set aside.
In a large bowl, whisk the melted butter and both sugars. Whisk for about 60 seconds.
Add the egg and whisk vigorously for 60-90 seconds. This helps get the shine on top of the blondies.
Whisk in the pumpkin puree and vanilla. Mix until smooth.
Switch to a rubber spatula, add the flour, pumpkin pie spice, cinnamon, and chocolate chips, stir until just combined. There should be no more flour streaks. Don’t over mix.
Pour batter into the prepared pan and evenly distribute the dough all the way to the sides of the pan. Hint: if you want a pretty top, add a little more chocolate chips to the top as a garnish before you put them in the oven.
Bake for about 25 to 28 minutes, or until done, depending on your oven. Insert a toothpick in the middle of the blondies. It should come out with a few, to no, crumbs.
Allow to come to room temperature, cut and serve. My favorite way to eat these blondies is straight out of the fridge, COLD!