Soak the lentils in cold water for 1-2 hours beforehand. Drain and rinse the beans under running water.
Cut carrots, celery and onions into small pieces. Heat oil in a saucepan over medium-high heat, put the vegetables and fry for about 5 minutes.
Throw minced garlic, cumin, coriander and paprika. Stir, fry for 1 minute and season with salt and pepper.
Add lentils and broth or water and bring to a boil. Reduce the heat, cover the pot a little and cook for 40–50 minutes until the beans are soft. In the middle of the preparation, place the tomatoes and thyme.
Add the spinach leaves to the soup and cook for another couple of minutes. Then salt and pepper to taste.