Preheat the oven to 350 degrees F (175 degrees C).

Heat 2 tablespoons oil in a Dutch oven over medium heat. Add rice and cook until golden, 5 to 10 minutes. Transfer toasted rice to a bowl.

Add remaining oil, onion, red bell pepper, and garlic to the Dutch oven. Cook over medium heat until tender-crisp, about 5 minutes. Transfer to a bowl.

Return toasted rice to the Dutch oven. Stir in broth, wine, water, oregano, cumin, salt, and pepper. Bring to a boil, about 5 minutes. Reduce heat and simmer until 1/2 the liquid has been absorbed, about 10 minutes.

Stir onion mixture, chicken, and tomatoes into the Dutch oven and cover with a lid.

Bake in the preheated oven for 30 to 45 minutes.

Stir in cilantro just before serving.