• Preheat the oven to 350ºF, and line an 8-inch baking dish with parchment paper. Spray with nonstick cooking spray.

Make the Cookie Dough:

• In a medium saucepan, melt the butter over medium-low heat. As the butter melts, it’ll start to foam, then turn a clear golden color. Continue to stir the butter, scraping up any browned specks from the bottom of the pan as it starts to brown. It should have a nutty aroma. Once browned and nutty, remove from the heat and immediately whisk in both sugars.
• Whisk the pumpkin and vanilla into the mixture until smooth. Add the flour, salt, baking powder, baking soda, and spices, and use a wooden spoon to stir everything together until just combined. If dough is still warm, allow it to cool to room temperature before stirring in the chocolate chips. Reserve a few tablespoons of chocolate chips for the very end. Transfer dough to another bowl.

Make the Brownie Batter:

• In the same saucepan over medium heat, melt the butter. Turn off the heat, and stir in the cocoa powder until smooth and glossy. Stir in the sugar. Add the egg and vanilla, stirring until fully incorporated. Stir in the flour and salt, followed by the butterscotch chips. Reserve a few tablespoons of butterscotch chips for the very end.
• Alternate spooning the brownie batter and cookie dough into the pan, smoothing out the top. Bake for about 30-33 minutes, or until edges are firm and golden. Immediately after removing brookies from oven, press the remaining chocolate and butterscotch chips into the top. Cool in pan for at least 45 minutes before cutting.