Preheat the oven to 350°F (175°C). Grease a 9×13 inch pan.
Mix flour, 2 tbsp sugar, and salt in a bowl. Cut in shortening until crumbly. Blend egg yolks with 1/2 cup milk and add to the flour mixture.
Roll out half the dough to fit the pan. Line the pan and brush with egg white.
Layer apples, sprinkle with sugar and cinnamon. Roll out the remaining dough, place on top, and brush with egg white.
Bake for about 35 minutes or until golden brown.
Mix icing ingredients in a bowl and drizzle over cooled bars. Cut into squares
