Grease an 8 by 10 pan or line with parchment paper.
Preheat oven to 350°F.
In a medium bowl, mix flour, baking powder, baking soda, salt, cinnamon, and pumpkin spice. Whisk all of the dry ingredients.
Add into the same bowl (you're welcome, don't dirty another bowl) oil, eggs, sugar, maple syrup, pumpkin puree, and vanilla. Mix well to combine.
Using a spatula, fold in white chocolate chunks.
Pour mixture into a greased or lined pan and bake for roughly 40 minutes or until center of pan is set. Check often and, as always, do not over-bake!
Allow to cool.
While cooling, make your frosting: Add cream cheese, butter, sugar, vanilla and salt into a medium bowl. Using a handheld or traditional mixer, mix until well blended and creamed.
Once she pan has cooled, cut into squares, then pipe icing on top of each bite.
Indulge and enjoy!