Wash the potatoes and cook in boiling water for 20-25 minutes. Wash thyme and rosemary, dab dry and divide into small twigs. Peel and finely dice the onions. Heat 3 tablespoons of oil in a saucepan. Steam onions and herbs for about 20 minutes.
Season with salt. Drain the potatoes, rinse with cold water and peel off the skin. Cut the potatoes in half lengthwise and place 3 halves in each mould with the cut surface facing upwards. Add onions and herbs. Clean, wash and cut the tomatoes into 12 slices. Put 1 tomato slice on each half of the potatoes. Cut the cheese horizontally and place it on the tomatoes. Brush with remaining oil. Sprinkle with pepper.
Put 1 tomato slice on each half of the potatoes. Cut the cheese horizontally and place it on the tomatoes. Brush with remaining oil. Sprinkle with pepper. Bake in the preheated oven (electric cooker: 250 ° C / gas: level 5) for about 15 minutes. Garnish with salad leaves