Preheat the oven to 350°F. Grease a 9X9 pan and line it with parchment paper. Set aside.
Put both chocolates and the butter in a saucepan and heat up until all is melted and smooth. Set it aside to cool down.
½ cup Dark chocolate, ½ cup Milk chocolate, ½ cup Butter
Whisk together flour, baking powder, salt, and spice, and set aside.
2 cups All-purpose flour, ¼ teaspoon Salt, 1 tablespoon Fall spice, 1 teaspoon Baking powder
Mix the pumpkin puree and the oil. Set aside.
1¼ cup Pumpkin Puree, ¼ cup Oil
Using the paddle attachment beat the eggs, two sugars, and vanilla extract until well blended and ligh.
4 Eggs, 1 cup Sugar, ½ cup Brown sugar, 1 tablespoon Vanilla extract
Using a rubber spatula, add the dry ingredients and gently mix.
Divide the batter into two bowls. Add the chocolate mixture to one bowl and mix. And add the pumpkin mixture to the other bowl and gently mix.
Drop dollops of chocolate batter into the prepared pan and alternate with the pumpkin batter Until both batters are used up.
Using the tip of a pairing knife, make swirls between two batters by dragging the pumpkin batter into the chocolate batter.
Tap the pan on the counter a couple of times then bake for 35-40 minutes. The edges start to set and brown slightly. Let cool down in the pan for 15 minutes, then transfer to the cooling rack to cool down. Let cool completely before cutting.