1. Heat oven to 350°F. Grease 13x9-inch pan.
2. In large bowl, beat together peanut butter, butter, brown sugar, granulated sugar and vanilla 5 minutes or until thick and creamy. Beat in eggs, flour and salt. Stir in 1 cup chocolate chips. Spread evenly into pan.
3. Bake bars 25 minutes or until lightly browned. Cool on wire rack; immediately sprinkle with remaining chocolate chips. Let stand 5 minutes. Evenly spread melted chocolate; sprinkle with toffee bar bits. Cool completely. Cut into bars to serve.
This recipe is recommended for 24 servings.