1. Preheat your oven to 350°F and prepare two 8-inch cake pans by greasing and flouring or lining with parchment paper.

2. In a large mixing bowl, whisk together the pumpkin puree, eggs, vegetable oil, granulated sugar, and brown sugar until smooth.

3. In a separate bowl, combine the flour, baking soda, pumpkin pie spice, and salt. Stir the dry ingredients into the wet mixture until just blended.

4. Divide the batter evenly between the prepared pans and bake for 30 to 35 minutes, or until a toothpick inserted in the center comes out clean. Cool the cakes completely.

5. To make the frosting, beat the butter until fluffy, gradually add the powdered sugar, then mix in the espresso and vanilla extract. Adjust consistency if needed.

6. Place one cake layer on a serving plate, frost the top, then stack the second layer and frost the entire cake. Garnish with extra spice or cinnamon swirl if desired.