Wash and thoroughly scrub the potatoes. Cook potatoes in boiling salted water for about 25 minutes. Wash, clean, quarter and seed the tomatoes. Cut tomato quarters into small cubes.
Cut the ham into fine strips. Grate cheese finely. Drain the potatoes, cut them in half lengthwise and place them in a greased casserole dish. Spread tomato cubes and ham on the potatoes.
Sprinkle cheese over it. Bake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 10 minutes until the cheese has melted. Clean, wash and cut the salad into pieces.
Peel, wash and roughly grate the carrot. Wash and slice the cucumber. Drain the corn on a sieve. Mix the salad ingredients. Mix vinegar, salt, pepper and sugar. Fold in the oil.
Arrange potato halves with the salad.