Preparation

• Preheat oven to 350ºF (177ºC). Line an 8x8 inch baking pan with parchment paper. Set aside.
• Melt the chocolate and butter in a saucepan over medium low heat until pieces are melted.
• In a large bowl use an electric mixer on medium speed to beat eggs until light yellow (about 5 minutes).
• Add sugar and blend on low until combined.
• Add vanilla and melted chocolate mixture to the egg sugar mixture then add flour and salt and beat just until all flour has been incorporated.
• Set aside while you prepare the cookie dough.
• In the bowl of a stand mixer with the paddle attachment, add cubed butter, brown sugar and granulated sugar.
• Turn mixer on low for a few seconds, then gradually increase speed to medium-high, mixing for about 3-4 minutes until well incorporated and fluffy.
• Turn mixer to low and add egg then vanilla.
• Mix on medium for about 30 seconds until well incorporated, stopping to scrape down the sides and bottom with a rubber spatula, as needed.
• With mixer off, add in flour, salt, baking soda and baking powder.
• Turn mixer on low and stir until just combined. Do not over mix. Add in chocolate chips.
• Take half of the cookie dough and press handfuls of it into the bottom of the prepared 8x8 inch baking pan.
• Pour all of the brownie batter over the mounds of cookie dough so that the brownie batter covers the bottom of the pan.
• Press the remaining half of the cookie batter into the top of the brownie batter, breaking it up by hand and inserting in patches, pressing it into the brownie batter so that the surface is fairly level.
• Bake for 40-45 minutes (until toothpick inserted in brownie portion near center comes out mostly clean with just a few crumbs).
• Allow to cool completely before removing from pan and cutting into squares.