In a large mixing bowl with electric mixer at medium speed, cream butter, sugars and egg yolk until light and fluffy.

In a separate bowl combine flour, cinnamon and salt. Add to creamed mixture and continue beating just until blended (the dough will be stiff). Spread dough evenly in an ungreased 14 1/2 x 10 1/2 inch jelly roll pan.

Beat egg white with fork just until foamy. Spread evenly on top of batter. Sprinkle with nuts and press lightly into batter. Bake for 35-40 minutes. Cut into bars while still hot. Let cool in pan. To freeze: Wrap well, label and freeze. Will keep up to 3 months in freezer.