Place one package of crescent rolls in a 9 X 13-inch baking dish coated with vegetable spray and press to seal the seams. Bake at 375 F for 8-10 minutes or until golden brown. Layer half of cheese slices on top of crust and then place all of corned beef slices on top. Combine sauerkraut and dressing in a small bowl and mix; spread mixture over corned beef. Place remaining cheese slices on top. Unroll remaining crescent rolls and place on top, sealing seams. Brush with beaten egg white and sprinkle with caraway seeds. Bake for 15 minutes or until crust is golden brown. Yield: 16-24 squares.