Heat oven to 180ºC F. Grease and flour 2, 23 cm round cake pans. In large bowl, combine all cake ingredients except crushed cookies at low speed until moistened; beat 2 minutes at highest speed. Gently stir in crushed cookies. Pour batter into prepared pans. Bake at 180ºC F for 25-35 minutes or until toothpick comes out clean. Cool 10 minutes; remove from pans. Cool completely. In small bowl, combine half cup of the powdered sugar, shortening, vanilla and 2 egg whites; blend well. Beat in remaining powdered sugar until frosting is smooth and creamy. Fill and frost cake.