In a large stockpot or Dutch oven, combine frying chickens, water, carrot, celery, barley, chicken bouillon, salt, pepper, and bay leaf.

Bring to a boil over high heat.

Reduce heat to low, cover, and simmer for 30 minutes.

Add leeks to the pot.

Return the soup to a boil, then reduce the heat again.

Cover and simmer until the chicken is cooked through, about 15 minutes.

Remove the chicken from the broth and let it cool slightly.

Remove the chicken meat from the bones and skin.

Skim any fat from the broth and remove the bay leaf.

Cut the chicken into 1-inch pieces.

Return the chicken to the broth.

Heat for about 5 minutes until warmed through.

Serve hot.