Begin by pouring the heavy whipping cream into a large mixing bowl and beat on medium-high speed until stiff peaks form, about 3-5 minutes.

In another bowl, combine the mascarpone cheese, powdered sugar, and instant coffee granules. Mix until smooth.

Fold in the pumpkin puree, pumpkin pie spice, and vanilla extract to the cream cheese mixture until fully combined.

Gently fold the prepared whipped cream into the pumpkin mixture until no white streaks remain.

Brew a strong cup of coffee and allow it to cool. Briefly dip each ladyfinger into the coffee and layer in a baking dish.

Spread half of the pumpkin cream mixture over the first layer of ladyfingers, then repeat with remaining ladyfingers and cream.

Cover and chill in the refrigerator for at least 6 hours, or overnight.

Before serving, sprinkle a light dusting of cinnamon on top and slice to serve.