Rinse and drain dry lentils or split peas. Do not presoak. For 1 pound lentils or split peas, in a large saucepan, combine with 5 cups water or broth. Bring to boiling; reduce heat and simmer, covered, about 30 minutes for lentils and 45 minutes for split peas.
One pound dry lentils yields 6 cups cooked lentils; one pound dry split peas yields 5-1/2 cups cooked split peas.