In a large bowl, whisk together the pumpkin puree, mascarpone cheese, heavy cream, powdered sugar, vanilla extract, and pumpkin spice until smooth and creamy.

Dip each ladyfinger into the cooled coffee for a few seconds to soak.

Layer half of the soaked ladyfingers in the bottom of a rectangular dish.

Spread half of the pumpkin mixture evenly over the ladyfingers.

Repeat with the remaining ladyfingers, adding another layer followed by the rest of the pumpkin mixture.

Cover with plastic wrap and refrigerate for at least four hours or overnight.

Dust with cocoa powder before serving, slice, and enjoy.