Preheat your oven to 350°F. Line a 9x9 baking dish with parchment paper and lightly spray with non-stick spray, then set aside.
In a small saucepan, melt the chocolate chips and butter over low heat, stirring occasionally until smooth. Remove from heat and let cool slightly.
In a stand mixer bowl, combine the sugar and eggs, mixing until well incorporated.
Add the flour, baking powder, and salt to the mixture. Stir just until everything is combined.
Divide the batter evenly into two bowls and set aside.
In a separate bowl, whisk together the pumpkin puree, oil, cinnamon, and pumpkin pie spice.
Add the pumpkin mixture to one bowl of batter and the cooled chocolate mixture to the other. Stir each until thoroughly mixed.
Alternately spoon the chocolate and pumpkin batters into the prepared baking dish. Once filled, use a knife to swirl the batters for a marbled effect. Sprinkle the remaining chocolate chips on top.
Bake for 40-45 minutes or until a toothpick inserted in the center comes out mostly clean.
Remove from the oven and let cool before serving.