1Preheat oven to 375°F. For the Brownie Batter, prepare brownie mix as directed on package, adding flour and vanilla. Set aside.
2For the Cookie Dough, mix flour, baking soda and salt in medium bowl. Set aside. Beat butter and sugars in large bowl with electric mixer on medium speed until light and fluffy. Add eggs and vanilla; mix well. Gradually beat in flour mixture on low speed until well mixed. Stir in chocolate chips.
3Drop Brownie Batter by scant tablespoons about 2 inches apart onto ungreased baking sheets. Top each with a rounded tablespoon of Cookie Dough, placing it slightly to the side of instead of directly on top of the brownie.
4Bake 8 to 10 minutes or until cookie is lightly browned and brownie is set. Cool on baking sheets 1 minute. Remove to wire racks; cool completely.