Wash the potatoes and cook covered for about 20 minutes. Quench, peel and press through a potato press while still hot. Let them cool down. Knead with egg yolk, 2-4 tbsp. flour, salt, pepper and nutmeg
Cut the cheese into 8 cubes. Divide the potato mixture into 8 portions and roll out each to a square (approx. 7 x 7 cm) on a floured work surface. Place one cheese cube on each. Fold the dough diagonally and press the edges firmly together. Chill for about 5 minutes.
Peel and finely chop the onion. Mix with vinegar, salt, pepper and sugar. Whip 2 tablespoons of oil into it. Clean, wash and drain the salads. Wash and halve the tomatoes. Mix both with the salad dressing
Fry the potato pockets in 2 tablespoons of hot oil for 2-3 minutes on each side until golden brown. Serve with salad