Danish Pastry Apple Bars

Preheat oven to 375 degrees F (190 degrees C.)
In a large bowl, combine flour and salt. Cut in shortening until mixture resembles coarse crumbs. Beat egg yolk in measuring cup and add enough milk to make 2/3 cup total liquid. Stir into flour mixture until all flour is damp. Divide the dough in half. On floured surface, roll half the dough into a rectangle and fit into a 9x13 inch pan.
In large bowl, combine apples, brown sugar, white sugar, cinnamon and nutmeg. Put apple mixture in pan. Roll out remaining dough and place over apples. Seal edges and cut slits in top dough. Beat egg white till frothy and brush on crust.
Bake in the preheated oven for 50 minutes, or until golden brown.