Preheat the oven to 200 °C top heat.
Press the still warm potatoes through the potato press into a bowl and mix with the chopped olives, crème fraîche, egg yolks and olive oil.
Now fold in the egg white and season to taste with salt and nutmeg.
Spread a quarter of the mixture onto a round baking tray (diameter 14 cm) lined with baking paper, spread evenly 5 mm thin and bake in a hot oven for about 5 minutes until the surface turns a golden brown colour.
Now again spread a part of the mixture 5 mm thinly on the already baked dough and bake the layer again in the oven until golden brown.
Repeat this process until the potato mixture is used up.
Cut the still warm potato and olive cake into 4 equally sized pieces, arrange them so that you can see the beautiful cross-section, and serve immediately.