Wash the apples, peel them and cut them first into 4 parts, removing the core, and then into very thin slices.
Put them in a bowl and sprinkle them with lemon juice.
In another bowl, beat the eggs with sugar and vanilla until the mixture is very light and fluffy.
Combine the baking powder and sifted flour and the grated lemon peel, then add a little at a time, milk and warm melted butter.
Finally, very gently incorporate the apples with a spatula, being careful not to break the slices.
Gently transfer the mixture into a mold, possibly hinged, covered with parchment paper, trying to level the surface.
Bake at 180 ° C in a preheated ventilated oven and cook for about 50 minutes, until the surface starts to brown.
Cool the invisible apple pie before turning it to serve and serve.
