Preheat your oven to 350°F (175°C) and prepare a 9x13-inch baking pan.
Melt the unsalted butter in a large saucepan over low heat, then stir in the granulated sugar until combined. Add eggs one at a time, mixing well after each addition, then add vanilla extract.
In a medium bowl, whisk together flour, cocoa powder, baking powder, and salt. Gradually incorporate this dry mixture into the wet ingredients, then fold in chocolate chips.
In a separate bowl, beat the cream cheese until creamy, then add pumpkin puree, powdered sugar, vanilla extract, and pumpkin pie spice, mixing until smooth.
Pour half of the brownie batter into the prepared pan, then add dollops of the pumpkin cheesecake mixture and swirl with a knife.
Pour the remaining brownie batter over the cheesecake layer and create swirls again.
Bake for 30-35 minutes, checking for doneness with a toothpick.
Allow to cool in the pan for 15 minutes, then lift out and cool completely on a wire rack before cutting into squares.
Notes
Serve warm with whipped cream and a sprinkle of cinnamon for added flavor.