1. Heat oven to 350°F.
2. Stir together flour, sugar and salt in large bowl; cut in butter until crumbly. Stir in 1 beaten egg. Press mixture evenly onto bottom of ungreased 13x9x2-inch baking pan. Bake 25 minutes.
3. Meanwhile, beat sweetened condensed milk, remaining 1 egg and maple flavor in medium bowl; stir in nuts. Sprinkle chocolate chips evenly over prepared crust. Gently spread nut mixture evenly over chocolate. Return to oven.
4. Bake 25 minutes or until golden. Cool completely in pan on wire rack. Cut into bars. Store tightly covered at room temperature. Makes 24 to 36 bars.