Peel shallots and potatoes. Wash and dice the potatoes. Wash ribs and pat dry. Rub with salt and chilli powder. Heat the oil in a roasting pan and fry the ribs on all sides.
Add shallots and potatoes. Deglaze with 1/4 liter vinegar and pineapple juice. Cover and braise in the preheated oven (electric cooker: 200 °C/ gas: level 3) for 45 minutes. In the meantime clean and wash the leek and cut it into thick rings, cut the chillies into narrow rings.
Add both to the ribs 20 minutes before the end of the cooking time. Add 1/4 litre water and ketchup. Before serving, season again with salt, sugar and the remaining vinegar.