Skor Bars

2 1/3 cup flour
2/3 cup packed light brown sugar
3/4 cup (1-1/2 sticks) butter or margarine
1 egg, slightly beaten
2 cups (12-oz. pkg.) HERSHEY'S Semi-Sweet Chocolate Chips, divided
1 cup coarsely chopped nuts
1 can (14 oz.) sweetened condensed milk (not evaporated milk)
1-1/3 cups (8 oz. pkg.) HEATH BITS 'O BRICKLE Toffee Bits, divided

Heat oven to 350°F. Grease 13x9x2-inch baking pan. Combine flour and brown sugar in large bowl. Cut in butter until mixture resembles coarse crumbs. Add egg; mix well. Stir in 1-1/2 cups chocolate chips and nuts; set aside 1-1/2 cups mixture. Press remaining crumb mixture onto bottom of prepared pan. Bake 10 minutes. Pour sweetened condensed milk evenly over hot crust; set aside 1/4 cup toffee bits. Sprinkle remaining toffee bits over sweetened condensed milk. Sprinkle reserved crumb mixture and remaining 1/2 cup chips over top. Bake 25 to 30 minutes or until golden brown. Top with reserved toffee bits. Cool completely in pan on wire rack. Cut into bars.