Soak the buns. Peel and finely chop the onions. Chop half of the olives finely. Slice or halve the remaining olives as desired. Peel garlic and chop finely as well.
Wash the lemon thoroughly and finely grate the peel. Knead the minced meat, squeezed bread roll, egg, half of the onions and lemon peel. Season well with salt, pepper and paprika. Form 24 small oblong meatballs from the minced meat mixture.
Heat the oil in a large pan and fry the meatballs in it at medium heat for about 8 minutes, turning several times. In the meantime, heat olive oil in a pan and sauté the remaining onions, garlic and oregano.
Stir in tomato paste, sweat briefly and deglaze with tomatoes and stock. Add remaining olives and ketchup, bring everything to the boil and simmer at low heat for about 4 minutes. Then season to taste with salt, pepper, sugar and paprika.
Put 3 meatballs on each skewer. Arrange 2 skewers on tomato and olive sauce on a plate. Serve garnished with oregano, lemon and black olives. Flatbread tastes good with it.