Preheat oven to 350 degrees.  Line a 11x7 inch baking dish with aluminum foil or parchment paper, leaving an overhang for easy removal. 

Melt the butter and the chocolate chips in the microwave at 1-minute intervals at 50% power until melted and smooth. Stir in the cocoa powder until dissolved. Stir in the brown sugar, granulated sugar, salt, eggs, vanilla extract, and flour. Spread 3/4 of the batter in the prepared pan. 

Using a stand mixer or a hand mixer on medium speed, beat the cream cheese and sugar until creamy. Reduce the mixer speed to low and add the egg and vanilla extract, mixing until combined. Using an offset spatula, spread the cream cheese mixture over the brownie mixture. 

Stir in 1 1/2 tablespoons cold water to the remaining brownie mixture.  Drop by rounded spoonfuls onto the cream cheese mixture spacing them equally apart. Using a knife or chopstick, swirl the brownie mixture into the cream cheese mixture, being careful not to go too deep into the bottom brownie mixture or to over-swirl. 

Bake for 35-40 minutes or until a toothpick inserted in the edges comes out fairly clean and a toothpick inserted in the center comes out slightly gooey.