Preheat the oven to 325°F (163°C) and line a 9x9-inch baking dish with parchment paper.

In a medium bowl, combine the canned pumpkin with cinnamon, ginger, and nutmeg. Stir well.

In a large bowl, beat together mascarpone and cream cheese until smooth. Gradually add sugar, flour, and vanilla extract. Incorporate egg yolks one at a time.

Reserve 1/2 cup of the cream cheese mixture, then fold in the pumpkin mixture to the remaining cream cheese until smooth.

In another bowl, whisk flour, cocoa powder, baking powder, and salt. Gradually mix into the wet ingredients.

In a separate bowl, mix melted butter with sugar until fluffy. Add eggs and vanilla, then fold in the dry mixture gently.

Spread half the brownie batter in the baking dish, dollop the pumpkin cheesecake mixture on top, and swirl with reserved brownie batter.

Bake for about 45 minutes until set. Cool completely in the pan, then refrigerate for at least 1 hour before slicing.