Preheat oven to 350°F. Spray 13 x 9 in. pan with vegetable pan spray.
In small bowl, combine flour and salt. In large microwave-safe bowl, melt butter and chopped chocolate. Stir in sugar, eggs and vanilla extract; mix well. Add flour mixture; mix until just combined. (Do not over mix.) Stir in chips. Spread into prepared pan.
Bake 25-30 minutes or until toothpick inserted in center comes out almost clean. Cool completely on rack before cutting.
Makes about 24 brownies.