Wash the potatoes well, make a slight circle-shaped cut in their narrowest part and boil in water until ready. Pull their peels off easily like you would a sock from the cut.
To form the perfect potato meatballs, I used metal cookie cutters. Fill them well with the potato mix, pressing slightly for a thicker consistency, wrap each filled cookie cutter with plastic wrap and put in the freezer for a few hours (or a few days even).
Take the frozen potato meatballs carefully out of the cookie cutters, dip them first in the mixture of beaten to foam eggs, then in the breadcrumbs, eggs again and arrange in a tray with oiled baking paper.
Bake about 10 min. in a preheated 482°F (250 °C) oven on the middle element with the fan on, then flip them over with BBQ tongs and leave to crisp for another 10 min.
For the topping, beat the yoghurt with the mayonnaise, add the dill, mustard seeds, pressed garlic clove, ground walnuts and salt to taste. Stir well and serve in a bowl or glass along with the potato meatballs.