In a large mixing bowl, add both flours and whisk together. Add the vanilla sugar, lemon zest, egg yolks and milk. Gently whisk to combine (do not over mix). Set aside to rest for 15 minutes (important, do not skip this step).
In a second bowl, add the egg whites, sugar and pinch of salt and using an electric hand beater, beat together until creamy (1 minute). Gently fold the egg white mixture into the rested dough.
Using a ladle, gently pour 3-4 ladles full of batter in circles onto the grill. Brown for 2 minutes, then using two spatulas, flip and bake on the other side for a few seconds, then tear into bite-sized pieces (using two spatulas). Continue cooking briefly, until golden brown. Then transfer to a plate for serving.
Serve the Kaiserschmarrn dusted with powdered sugar and apple sauce on the side. Enjoy!
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