Preheat oven to 400 degrees. Prepare bottom crust and settle into 23 cm-pie plate. Peel and slice apples. Mix together half cup of flour and half cup of granulated sugar; pour evenly into bottom pie crust. Arrange apples to form a nice heap. Sprinkle with second half cup sugar; cinnamon and nutmeg. Cut butter into chunks and place on top of apples spacing evenly. Top with second pie crust attaching at the edges. Brush top of pie crust with egg white and water mixture; sprinkl e with sugar. Bake at 200ºC or 50 minutes.