Beat the eggs with the milk, then add the flour, potato starch, and baking powder.
Melt the butter in a skillet and pour in the batter. Sprinkle in the raisins and cook until golden on the bottom. Tear the pancake into pieces using a spatula.
Cook for a few more minutes, then dust with powdered sugar.
Serve the pieces on a platter with a small bowl of jam in the center, made using Prestomarmellata Ar.pa according to the instructions on the packet.