Black Bottom Cookie Bars

Directions

1. 1
   Preheat oven to 350 F. Line an 8x8 baking dish with foil, allowing some foil to overhang the edges. (This makes it easier to take the bars out and cut them neatly at the end.) Lightly butter the foil and set the dish aside.
2. 2
   In a small saucepan, melt the butter over medium heat, and continue to cook until it is nutty and brown, about 5-6 minutes. Watch carefully, as it can go from fantastic and yummy browned butter to icky burnt butter very quickly. Remove it from the heat and allow to cool slightly.
3. 3
   In a large mixing bowl, combine the brown sugar and the sugar, then whisk in the browned butter. Whisk in the eggs and the vanilla. Set aside.
4. 4
   Combine the flour, salt and baking soda in a medium bowl, then add to the sugar/butter/egg mixture and stir with a wooden spoon or spatula to combine.
5. 5
   Divide the batter in half, and transfer half to the bowl that you mixed up the flour in. Add the cocoa powder and the chocolate chips to one of the bowls, and stir well to combine.
6. 6
   Spread the chocolate batter into the bottom of the prepared pan, pressing gently to form an even layer. If you are using nuts, sprinkle them on top of the chocolate layer, then spread the plain batter on top of that, smoothing gently.
7. 7
   Bake for 25-30 minutes, or until golden brown and a toothpick inserted in the center comes out clean. Cool completely (the bars may sink a bit in the middle as they cool ... no worries!). Then lift bars out of the pan using the foil edges, cut into small squares, and serve.
8. 8
   NOTE: Adapted from a recipe posted on the always drool-inducing Bake or Break blog.