Whisk together flour and water, set aside.
Beat egg and lemon juice, set aside.
Heat oil and add onion, celery, cilantro, parsley, turmeric, chili (if desired) and 1 teaspoon salt.
Sauté over medium/high heat until well-cooked and blended, about 10 minutes.
Add 1 quart of the stock, lentils, garbanzos and tomatoes, bring to a boil.
Reduce heat and simmer until lentils are tender but not too mushy, about 20-25 minutes.
Add remaining stock, chicken, 1 teaspoon salt, 1 teaspoon pepper and continue to simmer another 5 minutes.
While stirring slowly, stream in egg/lemon mixture, followed by half of the flour/water mixture.
Bring to a low boil. Stir in noodles.
At any point, add a bit of stock, water or flour mixture to desired consistency. The soup should be hearty and somewhat thick.
Stir in remaining 1/4 cup cilantro. Add salt to taste.