Finely chop the onion and garlic.
Heat the oil in a large saucepan, then sauté the onion over low heat.
Meanwhile, peel the sweet potato & carrots and cut them into chunks. Rinse the grains and lentils, set aside.
When the onion is soft, add the garlic, oregano and ground spices, then stir for 30 seconds. Add the tomato purée and stir for another 30 seconds, then add the bay leaf grains, lentils, sweet potatoes, carrots, bell pepper and bay leaf. Add about a litre of water and the stock pot and stock cube.
Bring to the boil, cover and gently simmer for about 45 minutes. Keep adding water if it’s becoming too thick.
Cut the frankfurters into 4 pieces each. Chop the herbs.
When the grains and lentils are tender, add the frankfurter and cook for another 3-5 minutes.
Stir in the fresh herbs and vinegar. Season with freshly ground pepper.
Serve with more vinegar or sour cream and fresh crusty bread.