Pumpkin Mascarpone: Beat whipping cream in a mixing bowl just until barely stiff peaks. In a separate mixing bowl, combine pumpkin, brown sugar, mascarpone, vanilla, cinnamon, and pumpkin pie spice until smooth. Fold in whipped cream, until combined.

Assemble: Add coffee (and liqueur if using) to a shallow bowl. Dip the lady fingers in the coffee (don't soak them--just quickly dip them on both sides to get them wet) and lay them in a single layer on the bottom of an 8x8'' or similar size pan.

Smooth half of the pumpkin mascarpone mixture over the top. Add another layer of dipped lady fingers. Smooth remaining pumpkin mascarpone over the top.

Dust cocoa powder over the top (I use a fine mesh strainer to do this).

Refrigerate for 3-4 hours or up to overnight before serving.