Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking pan or line it with parchment paper for easy removal.
In a large saucepan over low heat, melt the butter. Remove from heat and stir in the granulated sugar. Mix in the eggs one at a time, followed by the vanilla extract, mixing until fully incorporated.
In a separate bowl, whisk together the flour, cocoa powder, baking powder, and salt. Gradually add this mixture to the wet ingredients, stirring until just combined. Fold in the chocolate chips, ensuring an even distribution.
In a mixing bowl, beat the softened cream cheese until smooth. Mix in the pumpkin puree, powdered sugar, vanilla extract, and pumpkin pie spice until creamy and well combined.
Pour half of the brownie batter into the prepared baking pan. Spread it evenly. Next, add dollops of the pumpkin cheesecake mixture on top of the brownie layer. Use a knife or spatula to gently swirl the cheesecake mixture into the brownie layer.
Pour the remaining brownie batter over the cheesecake swirl. Again, use a knife to create swirls, incorporating some of the cheesecake layer into the brownie batter for a marbled effect.
Bake in the preheated oven for 30-35 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs (not wet batter).
Allow the brownies to cool in the pan for at least 15 minutes before lifting them out using the parchment paper. Let them cool completely on a wire rack before cutting them into squares.
Notes
Serve warm with whipped cream and a sprinkle of cinnamon for added flair.