Preheat oven to 350°F. Prepare 9 x 13 inch baking pan by spraying with nonstick spray.
Prepare brownie mix as directed on the box, stirring in the espresso powder (if using) with the mix before adding eggs, oil, and water. Follow the package directions for your brownie mix. Fold in 1 cup mini chocolate chips.
In another bowl, with electric mixer, beat cream cheese, egg, butter, sugar, flour, and vanilla together until smooth. Fold in ½ cup mini chocolate chips.
To assemble: Pour half of brownie batter into pan. Spoon the cream cheese mixture over the first layer of brownie batter. Spread it out the best that you can so that the cream cheese mixture pretty evenly covers the brownie batter. Spoon on the remaining half of the brownie batter to cover the cream cheese mixture.
Bake 35 to 40 minutes. Check with toothpick inserted about two inches from the side. There shouldn’t be batter clinging to the toothpick.Serve warm or at room temperature.
