Preheat oven to 350°F and line a 9x5 loaf pan with parchment paper leaving at least as inch overhang on the long sides. Then lightly grease the pan with nonstick cooking spray.
In a stand mixer fitted with the paddle attachment, cream together the softened butter and granulated sugar until light and fluffy. About 1-2 minutes.
Beat in the eggs, one at a time, and scraping sides of the bowl as needed. Then beat in the vanilla extract.
Add the baking powder, cinnamon, salt and all purpose flour. Mix on low speed just until incorporated.
Add the pumpkin puree and beat until everything is evenly combined but being careful not to overmix.
Spoon the cake batter into the prepared loaf pan and then spread it into an even layer.
Bake the cake on center rack in preheated oven for 55-60 minutes or until toothpick or cake tester inserted in center comes out clean.
Let cake cool in pan for 15 minutes then remove to wire rack and cool completely.