Wash the potatoes thoroughly, cut in half, mix with 1-2 tablespoons of oil and place on a baking tray. Season with coarse salt and pepper and cook in the preheated oven (electric cooker: 200 °C/ circulating air: 175 °C/ gas: level 3) for approx. 15 minutes.
Peel and halve the shallots, add them to the potatoes on a baking tray and bake for another 15-20 minutes. In the meantime peel garlic, press it through a garlic press, mix with vinegar and season with salt, pepper and sugar.
Add 5 tablespoons of oil. Clean, wash and drain the rocket. Wash and slice the tomatoes. Wash the meat and dab dry. Brush a grill pan with oil. Grill the meat in it in 2 portions, depending on the thickness, on each side for about 2 minutes, season with salt and pepper.
Remove the potatoes and shallots, let them cool down briefly and put them into a bowl. Heat the vinaigrette, add the rocket and tomatoes to the potatoes, mix and serve with the lamb chops.