Make sure the lentils are free of any dirt. Wash them several times.
Sauté the onion in a little bit of olive oil, then add the garlic and stir a bit more. Add the lentils, the tomato paste and the liquid. Let it boil, then cover and simmer for 30 min, stirring frequently. Add the potatoes and the corn and let simmer until the lentils dissolve and the soup is thick and opaque. If you need more liquid, add some water.
Note: I always end up adding water toward the end. So you might want to consider adding a cup of water in the beginning.
This soup is best served with crunchy bread. You can also add any vegetable you like but the potatoes and the corn are essential for texture.
