MIX peanut butter, butter, icing sugar, egg yolks and flour until blended and smooth. Spread evenly into greased 9 inch (23 cm) square pan. Bake at 350°F (180°C) for 15 minutes or until golden.
SPREAD jam over base.
BEAT egg whites and cream of tartar until soft peaks form. Gradually beat in sugar. Fold in nuts. Spread over jam layer. Bake at 350°F (180°C) for 20 to 25 minutes or until lightly browned. Cool and cut into bars.