MIMI SHERATON'S FAVORITE CHICKEN SOUP AND GREEK AVGOLEMONO SOUP

MIMI SHERATON'S FAVORITE CHICKEN SOUP

''Root vegetables are essential to this soup. If parsley root is unavailable, add an extra inch or two of parsnip. For a richer, heavier soup, use the veal knuckle. Tomato, white or sweet potato, and garlic are used in some Jewish homes, but not in mine. Try any or all if you like, but the result will then not be ''My Favorite.'' Deviate, and you're on your own. This soup usually is a first course, without chicken but with matzoh balls, kreplach, rice or any noodle-based garnishes. To be truly ''My Favorite Soup'' this must be made with a fowl. Do the best you can.''

5- to 6- pound fowl, or 7 to 8 pounds broiling or frying chickens, with neck and all giblets except liver

Veal knuckle bone (optional)

10 to 12 cups water, or more as needed

2 large carrots, scraped and quartered

2 celery stalks with leaves, whole or cut up

1 medium onion

3 Italian parsley sprigs

1 small parsnip, scraped and cut in half

1/2 small celery root (celeriac), peeled

A 2- to 3-inch length of parsley root (petrouchka), scraped and cut in half

1 medium leek, green and white portions, split and well washed

Salt and white pepper, to taste

Pinch of sugar, if needed

Minced fresh parsley and/or dill

Optional additions:

1 or 2 tablespoons cooked green peas per portion

1/4 cup cooked rice per portion

Matzoh Balls or kreplach

Noodles or soup nuts

The chicken may be cooked whole, if pot is large enough, or quartered. Place in a close-fitting 6- to 7-quart enameled or stainless-steel soup pot along with giblets and veal knuckle, if you are using it. Cover with 10 cups of water if you use broilers, or 12 if you use a fowl. Cover and bring to a boil. Reduce to a simmer and skim foam as it rises to the surface.

When foam subsides, add all other ingredients except pepper and sugar, and with just 1 teaspoon of salt. Let chicken simmer, partly covered, until very tender and just loosening from the bone, about 1-1/4 hours for broilers or 2-1/2 to 3 hours for a fowl. Add more water during cooking if chicken is not seven-eighths covered. Turn chicken 2 or 3 times during cooking. Add salt gradually, tasting as cooking progresses.

Remove chicken, giblets, and bones and set aside. Pour soup through a sieve. Rinse pot and return soup to pot if it is to be served immediately or within 2 or 3 hours. Discard vegetables. Bones can be discarded or nibbled on. Chicken will be good only to be added in small spoon-size pieces to soup, or for chicken salad or pie.

The soup can be made ahead up to this point and stored in a ceramic or glass bowl. Cool thoroughly, uncovered, then cover and store in refrigerator for up to 2 days. Skim off solidified fat just before reheating. Add pepper and sugar when reheating. Store chicken separately, covered, in a bowl.

Serve soup very hot, with any of the suggested additions. Garnish with parsley or dill.

Serves 6 to 8.

- From ''The Whole World Loves Chicken Soup: Recipes and Lore to Comfort Body and Soul,'' by Mimi Sheraton (Warner Books, 230 pp., $22.95)

GREEK AVGOLEMONO SOUP

This recipe is a variation on the Greek classic.

1 large onion, cut into small dice

4 cloves garlic, finely chopped

1/4 cup olive oil

1-1/4 teaspoon dried thyme

3/4 cup long-grain white rice

12 cups strong chicken stock

4 large eggs, lightly beaten

2 cups chopped, cooked white chicken meat

1/2 to 3/4 cup fresh lemon juice, to taste

Salt and pepper, to taste

1/2 cup finely chopped parsley

In a heavy-bottomed, 4-quart saucepan, cook the onion and garlic in the olive oil over moderately low heat for 10 minutes, stirring frequently. Add the thyme and rice and cook one minute. Add the chicken stock and bring to a boil over high heat. Reduce the heat to moderate, and cook 15 to 20 minutes, or until the rice is tender but not mushy.

Spoon 1-1/2 cups of the hot soup into a large bowl. Slowly add the eggs to the bowl of soup, whisking constantly to prevent eggs from curdling. Add 1-1/2 additional cups of soup to the egg mixture, whisking constantly. Add the egg-soup mixture to the pot of soup, stirring constantly. Add the chicken, lemon juice, salt, and pepper and mix well. Garnish each portion with parsley. Makes about 14 cups.

- Adapted from ''The Chicken Soup Book,'' by Janet Hazen (Chronicle Books, 1994)