Heat the olive oil in a large pot over medium heat. Add the chicken thighs and cook until they are browned on all sides.
Add the diced onion and bell pepper to the pot and cook until they are soft, about 5 minutes.
Add the rice, chicken broth, water, cumin, paprika, salt, and black pepper to the pot. Stir well to combine.
Add the sofrito, cilantro, and achiote to the pot and stir to combine.
Bring the mixture to a boil, then reduce the heat to low and simmer, covered, for about 20 minutes or until the rice is tender and the chicken is fully cooked.
Stir in the frozen peas, green olives and cook for an additional 5 minutes.
Garnish the arroz con pollo with chopped fresh cilantro, if desired, and serve hot. Enjoy!