Mix the natural yoghurt with water until it has completely dissolved. Remove a little and mix with the flour. Put aside.
Peel and chop the garlic. Melt the butter and add the garlic and powdered bread and sweat while stirring. Be careful not to turn brown.
Then add the pre-cooked tripe and keep stirring. Deglaze with the yogurt-water mixture and turn the stove down to medium heat. Keep stirring. When the soup starts to boil, stir in the flour-water mixture. The soup no longer needs to be stirred when it is boiling. Continue cooking over medium heat.
Sprinkle with black pepper and serve with flatbread.