Preheat your oven to 350F and line a baking tray with parchment paper.
Combine in a large mixing bowl, the softened butter and brown sugar. Use a hand mixer to cream and then mix in the egg. Keep mixing until light and fluffy.
½ cup Unsalted Butter, ½ cup Brown Sugar, 1 large Egg
Add the pumpkin puree and the maple syrup to the butter mixture. Mix until combined. Set aside.
½ cup Pumpkin Puree, ¼ cup Maple Syrup
Whisk together in a separate bowl; the flour, baking powder, salt, cinnamon, and nutmeg. Mix until well combined.
2½ cups All Purpose Flour, 2 teaspoon Baking Powder, ½ teaspoon Salt, 2 teaspoon Cinnamon, ½ teaspoon Ground Nutmeg
Add the dry ingredients to the bowl of wet ingredients, along with the chopped walnuts. Mix until just combined. Use a rubber spatula to make sure there is no more flour mixture in the bottom of the bowl.
½ cup Walnut Pieces