1. Heat oven to 350 degree F. Line a 9-inch-square baking pan with nonstick foil, leaving extra foil on 2 side edges.
2. Place chopped chocolate and butter in a medium-size microwave-safe bowl. Microwave on high for 1 minute. Stir and microwave for an additional 30 seconds. Stir until smooth.
3. Whisk sugar, eggs and vanilla into chocolate mixture. Stir in flour and salt until incorporated. Fold in nuts and chips.
4. Spoon batter into prepared pan. Bake at 350 degree F for 22 minutes or until toothpick inserted in center of brownie comes out with a few moist crumbs clinging. Remove from oven and cool briefly on a wire rack.
5. Use the overhanging foil to lift brownie from pan. Cut into 16 squares.