Preheat the oven to 350°F (180°C). Grease or line an 8x8 baking dish.
Add the vegan butter to a large mixing bowl and melt it in the microwave for about 30-45 seconds.
Quickly mix in the sugar while the butter is hot so that it melts the granules.
Mix in the pumpkin purée. Then, gently stir in the flour, baking powder, and pumpkin pie spice.
Scoop out 1/3 cup of this orange pumpkin brownie base and set it aside for now.
To the large mixing bowl, gently stir in the cocoa powder and vanilla extract. Once combined, fold in the chocolate chips.
Spread the chocolate brownie batter evenly in the pan. Scoop the pumpkin mixture on top and slightly swirl it in.
Bake the brownies for about 25 minutes or until the edges begin to firm up. It's okay if the center looks soft because it will set as it cools.
Sprinkle flaky salt on top (optional). Let this cool down for 10 minutes before slicing. Enjoy!