In a small bowl, combine flour, baking powder and salt; set aside. In a large bowl, beat butter, brown sugar and vanilla with an electric mixer on medium speed about 3 to 5 minutes until mixture is creamy and has turned almost white. Add eggs, one at a time, beating well after each addition. Gradually beat in flour mixture. Stir in chocolate chips. Spread dough evenly onto a parchment paper-lined 14" round pizza pan. Bake at 350 degrees for 30 to 40 minutes, until edges turn golden. Let cool for 10 minutes in pan before removing. Cool completely.