Prepare the Chicken Broth In a large pot, add 8 cups of water, chicken pieces, onion, halved garlic head, bay leaves, and salt. Bring to a boil, then reduce to a simmer. Cook until the chicken is tender, about 40–50 minutes. Skim off any foam for a clearer broth. Make the Tomato Sauce In a blender, combine Roma tomatoes, small piece of onion, garlic clove, chicken bouillon, tomato bouillon, oregano, and ½ to 1 cup of hot broth. Blend until smooth.Strain the sauce into the pot and stir to combine.
Add the Vegetables Add the corn, carrots, and potatoes to the pot. Simmer for about 15 minutes, until potatoes are nearly tender.
Finish the Soup Add the zucchini and cilantro. Cook for another 5–7 minutes, or until all vegetables are cooked but still hold their shape
Taste and Adjust Check seasoning and adjust with more salt or bouillon if needed.
Serve Ladle hot soup into bowls and serve with warm corn tortillas, lime wedges, sliced avocado, or a scoop of rice on the side.