Heat the oil in a large stock pot or Dutch oven over medium heat. Add the diced onion, bell pepper, and garlic. Sauté 3–5 minutes until fragrant and slightly softened.
Add the chicken broth, water, lime juice, fire-roasted tomatoes, chili powder, cumin, oregano, salt, pepper, and coriander. Stir well to combine.
Add the adobo chicken and bring the mixture to a boil over medium-high heat.
Reduce heat to medium-low, cover, and simmer for 30 minutes, stirring occasionally.
Taste and adjust seasoning if needed.
Serve hot, garnished with fresh cilantro, if desired.