1 cup (2 sticks) cold, unsalted butter, cubed
3/4 cup sugar
3/4 cup brown sugar
2 large eggs
½ cup dark cocoa powder ( I used Hershey's Dark)
1 1/4 cups all-purpose flour
1 cup cake flour
¼ tsp. coarse salt
3/4 tsp baking soda
1/2 tsp baking powder
1 small dash cinnamon (optional)
1 small dash cinnamon (optional)
2½ cups semi-sweet chocolate chips
Directions:
Preheat the oven to 350˚ F. Line baking sheets with parchment paper or silicone baking mats. In the bowl of an electric mixer, combine the butter and sugars. Beat together on medium-high speed until light and fluffy, 2-3 minutes. Blend in the eggs one at a time, scraping down the bowl as needed. Mix in the cocoa powder until well blended. Add the flour, salt and baking powder and cinnamon to the bowl and mix on low speed just until incorporated. Fold in the chocolate chips with a spatula. Transfer the dough to a work surface and knead briefly by hand to be sure the ingredients are well combined.
Roll the dough into balls and flatten just slightly into a disc. Place on the prepared baking sheets, a few inches apart. Bake 8 minutes making sure the middle looks a bit undone. Let cool on the baking sheets 5-10 minutes, then transfer to a wire rack to cool completely.