Wash the potatoes and cook in boiling water for about 15 minutes. Then rinse with cold water, peel and leave to rest. Knead minced meat, egg, breadcrumbs and mustard. Season with salt and pepper. Form into 4-5 cm large meatballs. Peel and halve the onions.
Clean, wash and chop the peppers. Cut potatoes in half. Put prepared ingredients on skewers. Cook on the hot grill while turning for about 10 minutes. Sprinkle potatoes with coarse salt, coloured pepper and chopped thyme shortly before the end of the grilling time. Spread the skewers with olive oil and serve