Soak the lentils in cold water one or two hours before.
Finely chop the onion, parsley, and coriander.
Roughly chop the tomatoes. Do the same with the celery stalks. Place everything in a chopper or blender. Add a veal bouillon cube and blend finely.
Pour a drizzle of olive oil into a large pot, add the onion and herbs, then the blended mixture. Add the drained lentils.
Cover everything with the tomato sauce from the can of peeled tomatoes and water. Add salt and turmeric.
Cover and cook for 1 hour.
Meanwhile, dilute the tomato paste in 2 liters of water, then add the flour while whisking. Add this to the soup and mix. Let it cook and thicken.
At the end of cooking, add the vermicelli and the drained chickpeas. Turn off the heat after 5 minutes.