Soak the beans overnight in enough water to cover.
Drain and rinse well.
Place the beans in a large saucepan, add the stock and bring to the boil.
Reduce the heat, cover partially and simmer for two hours.
Mash a quarter of the beans using a potato masher. This will thicken the soup.
Add the bay leaves and cassia or cinnamon.
Heat the oil in a pan and fry the mustard seeds in the oil until they begin to pop.
Crush the seeds with the back of a spoon.
Add the garlic, onions and pepper and sauté until the onions are golden brown.
Add the onion mixture to the bean mixture and stir well.
Add the tomato paste, parsley, thyme, rosemary and lemon juice and season with salt.
Cover and simmer over low heat for one hour.
Add more water if necessary.
Serve with cheese dumplings and fresh herbs
Sift together 180 ml cake flour, 5 ml baking powder and 5 ml salt.
Whisk together 1 egg and 75 ml milk and add to the flour mixture along with 125 g grated Cheddar cheese.
Mix to form a stiff dough.
Drop teaspoonfuls of the dough in the simmering soup, cover and cook for 10 minutes.