Preheat oven to 350F. Grease and line a loaf pan with parchment paper. You wan to make sure the parchment paper hangs out a bit around the long edges so the loaf so you can easily remove the bread.
In a medium sized bowl whisk together flour, pumpkin pie spice, cinnamon, espresso powder, baking powder, baking soda, and salt. Set aside.
In a large sized bowl combine the eggs, brown sugar, white sugar, oil, pumpkin puree, vanilla extract, and milk.
Add the dry ingredients into the wet and fold together using a rubber spatula. You want to be careful not to over mix. Once you can no longer see any flour stop mixing.
Pour batter into your lined loaf pan. Bake for 55-60 minutes or until a toothpick inserted into the centre of the bread comes out clean. Allow loaf to fully cool to room temperature before removing it from the pan.
With an electric mixer or stand mixer cream butter for 4 minutes.
Add in the powdered sugar 1 cup at a time, mixing in between each added cup.
Add in heavy cream and espresso powder.
Mix for 4-5 minutes on high speed until light and fluffy.
Add the buttercream on top of the cooled pumpkin cake. Lightly dust with cinnamon (optional)
