Lemon Chicken Rice Soup

Lemon chicken Rice Soup.
Ingredients.
1 package of boneless skinless chicken.
1/2 cup of olive oil.
1 medium size onion.
6 carrots.
1/2 cup of celery flakes or 1 medium celery stick cut in small pieces.
1 cup of slow cooking rice.
Salt, pepper.
Avgolemono sauce.
5 eggs.
200 gr (3/4 cup) of lemon juice.
1 tablespoon of all-purpose flour.
Salt.