For the dough, wash 300 g potatoes and cook covered in water for about 20 minutes. Then drain, rinse, peel and press the still hot potatoes through a potato press.
Crumble yeast into 1⁄4 l lukewarm water and dissolve in it with the sugar while stirring. Let stand for about 5 minutes until the yeast water starts to bubble. Put 500 g flour into a mixing bowl and press a depression in the middle.
Pour in the yeast water and mix with some flour to a pre-dough. Cover and leave to rise in a warm place for about 15 minutes.
Finely grate the Parmesan cheese. 1 1⁄2 Add a teaspoon of salt, 5 tablespoons of olive oil, potatoes pressed through and 100 g of parmesan cheese to the pre-dough. Mix everything with the dough hooks of the mixer to a smooth dough.
Cover and leave to rise in a warm place for about 45 minutes.
Grease baking tray, dust with flour. Knead the dough once again on a floured work surface. Roll out on the baking tray. Cover and leave to rise in a warm place for about 30 minutes.
Preheat oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see manufacturer). Grate the raclette. Wash and peel 400 g potatoes and slice them into thin slices. Cover dough with potato slices and sprinkle with raclette.
Bake in the oven for about 25 minutes.
For the pesto, wash the parsley, shake dry and pluck the leaves. Peel garlic and chop coarsely. Coarsely chop the nuts. Puree parsley, nuts, garlic and 50 g parmesan cheese with a hand blender.
Let 100 ml olive oil run in. Season with salt and pepper. Arrange potato cake with pesto.