Gâteau Invisible (invisible apple cake) is a French dessert featuring thinly layered apple slices baked in a custard-like batter. My version is spiced with cinnamon, cardamom, and nutmeg, giving it an American twist.
Whisk eggs in a medium bowl, then add milk, melted butter, and vanilla until incorporated. Add both sugars, flour, and spices, and whisk until smooth. Set aside.
Peel and core apples, then slice thinly with a mandoline or a sharp knife. Slice each apple ring in half, then fold into the cake batter. Continue until all the apples are folded into the batter.
Butter the ends of a loaf pan, then insert an 8" wide strip of parchment paper with the extra hanging off the sides so that it creates a sling. Layer apple slices tightly into the pan, pressing down occasionally to compress.
Continue layering the apples until they are used up. Pour remaining batter evenly over the top. Place the pan on a baking tray to catch any juices, then bake in a preheated 350°F oven for 1 hour, or until the top is golden brown and a toothpick inserted in the center comes out clean and meets no resistance.
Run a knife along the buttered edges of the pan to loosen the cake, then lift out using the sling created by the parchment paper. Dust with powdered sugar and allow to cool before slicing and serving.
Notes
If the cake browns before completely cooking through, cover with foil for the remainder of the baking time.
If possible, use a mandoline to slice the apples paper-thin. The thinner they are, the more invisible they will appear once baked.
When layering the apple slices, press firmly. This creates those gorgeous compressed layers.
For added crunch, sprinkle with slivered almonds before baking.
The cake sets as it cools. Slice too soon and it will fall apart. Chill in the fridge for an hour for cleaner cuts.
Store in the fridge in an airtight container for up to a week.