1Heat oven to 325°F. Lightly spray 15x10x1-inch pan with cooking spray.
2In large bowl, stir together peanut butter, eggs and vanilla. Stir in brown sugar until blended. Add Bisquick mix and 3/4 cup of the chocolate chips, stirring just until dry ingredients are moistened. Spread mixture in pan.
3Bake 20 minutes or until golden brown. Sprinkle with remaining 1 1/4 cups chocolate chips; let stand 5 minutes or until chocolate is melted. Spread melted chocolate evenly over top. Cut into 4 rows by 3 rows, then cut each bar in half to form a triangle.