Preheat oven to 375°F (190°C).
In a sheet pan, combine water, sliced onions, peppers,cilantro, minced garlic, butter, and liquid smoke (if using).
In a small bowl, mix together chicken bouillon powder, salt, garlic powder, smoked paprika, black pepper, cayenne pepper, and bay leaf.
Lightly coat the chicken breasts with olive oil and barbecue sauce, then generously season both sides with the dry spice mixture.
Place the seasoned chicken breasts over the onion mixture in the sheet pan.
Cover the sheet pan tightly with foil.
Roast in the preheated oven for 30-45 minutes, or until the chicken is fork-tender and the onions are browned.
Once cooked, remove the pan from the oven. Discard the bay leaf.
Using two forks, shred the chicken directly in the pan, allowing it to mix with the cooked onions and pan juices.
Stir in extra barbecue sauce optional