Rice and lentils

Clean the lentils, soak them in cold water for 12 hours, remove any which have risen to the surface, as they are rotten. Cook the lentils in a saucepan in about 1 litre of water, celery and some salt for about ½ hour. Separately, prepare finely minced garlic, onion, celery and cook with 4 tbs. of oil. When they have browned, add some tomatoes. Let the sauce thicken and add the lentils with some of their cooking water.  Boil again and add the rice, cooking it for about 20 minutes. The soup should be quite thick.