Peel and finely dice the onion and garlic. Wash the marjoram, shake dry. Put something aside for garnishing. Pluck the rest of the leaves from the stalks and chop. Knead minced meat, egg, onion, garlic, marjoram and mustard, season with salt and pepper.
Wash the tomatoes, cut off the upper third. Hollow out the tomatoes. Wash the peppers, cut a lid off lengthwise. Clean the bell peppers. Cover sausages with minced meat (approx. 75 g per sausage). Fill paprika and tomatoes with minced meat (approx. 50 g per piece).
Form 4 meatballs from the remaining mince. Chop the olives and mix with 75 g ricotta. Spread over the meatballs. Sprinkle with parmesan. Put everything on a baking tray lined with baking paper. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 20-25 minutes.
Peel and wash the potatoes and cut them lengthwise into slices. Heat the oil in a pan. Fry the potatoes for 15-20 minutes while turning. Season with salt, pepper and sweet-sour sauce. In the meantime, mix 175 g ricotta and sour cream.
Wash herbs, shake dry. Cut chives into fine rolls, chop parsley. Stir into the ricotta cream. Season with salt and pepper. Take the chopping trio out of the oven, cut the sausages into pieces and put them on skewers.
Arrange everything on a plate, garnish with marjoram. Add ricotta cream and potato wedges.