(Estelle's recommends only using a portion of this)
Preheat oven to 350 degrees F. Combine flour and salt in a medium sized mixing bowl. Cut in butter with pastry cutter until you have a crumbly mixture. In a separate bowl, beat two egg yolks until creamy yellow. Add milk to the yolks to equal 2/3 cup. Add this to your flour mixture and toss lightly. Divide this mixture in half and pat 1/2 of the flour mixture into a greased 9" x 13" baking dish. Sprinkle with the crushed cereal.
Spread the apple pieces over this mixture and then sprinkle with the sugar and cinnamon. Spoon the remaining flour mixture over the apples and pat down firmly. Brush with the two beaten egg whites. Bake for 1 hour at 350 degrees F. Drizzle the icing over the bars and then cool slightly. Ready to serve....perhaps a little vanilla ice cream.....oh yes, please!