Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   1      cup           lentils -- dried quick-cooking
   1      tablespoon    vegetable oil
   6      cups          water
   2      tablespoons   unbleached flour
   2                    bacon; slices -- diced
   1      tablespoon    vinegar
   1                    leek or green onion -- *
   4                    frankfurters -- thickly sliced
   1      large         carrot -- finely chopped
   1      tablespoon    catsup -- tomato
   1      stalk         celery -- finely chopped
   1      teaspoon      salt
   1                    onion -- finely chopped
     1/4  teaspoon      black pepper

Preparation:

* Leek or Green Onion should be finely chopped. Wash the lentils thoroughly. In a 2 1/2-quart saucepan bring 6 cups of water to a boil. Add the lentils, bacon, leek or green onion, carrot and celery. Simmer, partially covered, for 30 to 40 minutes. Meanwhile in a frying pan, sauté chopped onion in vegetable oil until soft. Sprinkle flour over onion, and stir. Lower heat, stir constantly, and cook until the flour turns a light brown. DO NOT burn flour. Stir in 1/2 cup of hot lentil soup into the browned flour; beat with a wire whisk until well-blended. Beat in vinegar. Add contents of frying pan to lentil pan and stir together. Cover and simmer for 30 minutes or until lentils are soft. Add the frankfurters and catsup. Cook to heat frankfurters through. Season with salt and pepper and serve hot.