Preheat oven to 350°F and grease a 10x15 baking pan. Line the pan with parchment paper, leaving enough overhang on the sides for easy removal.
In a large bowl, whisk together flour, baking powder, baking soda, salt, cinnamon, and pumpkin spice. Set aside.
In a separate bowl, whisk together oil, eggs, brown sugar, granulated sugar, pumpkin, and vanilla extract until well combined.
Pour the wet ingredients into the bowl with the dry ingredients. Use a mixer or whisk to combine until the batter is thick and fully mixed.
Spread the pumpkin batter evenly into the prepared baking pan. Bake for 28-35 minutes, or until a toothpick inserted into the center comes out clean.
Ensure the bars are fully cooked by inserting a toothpick into the center. If the top or edges brown too quickly, tent with aluminum foil during baking.
Once baked, remove the pan from the oven and place it on a wire rack to cool. Allow the bars to cool completely, approximately 45 minutes. For faster cooling, transfer to the refrigerator.
Once cooled, lift the bars out of the pan using the parchment paper overhang. Slice into bars of desired size and serve.
For added indulgence, top the pumpkin bars with cream cheese frosting, whipped cream, or a dusting of powdered sugar.
Store leftover pumpkin bars in an airtight container in the refrigerator for up to 5 days. They can also be frozen for longer storage.
Savor the warm flavors of pumpkin and spices in these delicious bars, perfect for autumn gatherings or a cozy treat at home.
Spread the joy by sharing this scrumptious pumpkin bars recipe with family and friends!