1. Preheat your oven to 350 F (175 C). Line a 9×13 inch baking pan with parchment paper, leaving an overhang on the sides to easily lift the bars out later. Prepare the brownie batter according to the package directions for a fudgy brownie. Pour about two-thirds of the brownie batter into the prepared pan and spread it evenly. Reserve the remaining one-third of the batter.

2. In a medium mixing bowl, beat the softened cream cheese with an electric mixer until smooth and creamy, with no lumps. Add the pumpkin puree, granulated sugar, pumpkin pie spice, egg, and vanilla extract. Beat until well combined and smooth.

3. Carefully pour the pumpkin cream cheese mixture over the brownie batter in the pan, spreading it gently to form an even layer.

4. Take the reserved one-third of the brownie batter and drop spoonfuls of it over the pumpkin layer. Don’t worry about perfect placement; irregular drops are fine.

5. Using a knife or a skewer, gently drag it through the layers in a swirling motion. You can make figure-eights or random swirls to create a beautiful marbled pattern. Be careful not to overmix, as you want distinct layers of brownie and pumpkin.

6. Place the pan in the preheated oven and bake for 35-40 minutes, or until the edges are set and a toothpick inserted into the brownie portion comes out with moist crumbs, but not wet batter. The pumpkin layer might still have a slight jiggle in the center, which is normal.

7. Remove the pan from the oven and let the bars cool completely on a wire rack. For the cleanest slices and best texture, refrigerate the bars for at least 1-2 hours (or even overnight) before lifting them out of the pan using the parchment paper overhang and cutting them into squares.