Season the chicken with paprika, salt and pepper to taste.
Turn on the Instant Pot ON and select "sauté", adjust to more. Heat 2 tablespoons of oil. Add the chicken and cook for 5 - 8 minutes or until chicken is lightly browned and no longer pink. Remove chicken from the Instant Pot and reserve.
Add the remaining 2 tablespoons of oil to the Instant Pot. Sauté onion, peppers, garlic, and green onion for 3-5 minutes, or until the onion is translucent. Add the uncooked rice and toast for 1 minute, stirring constantly.
Add chicken broth, deglaze the pot using a wooden utensil with a flat head to scrape all of the stuck bits off of the bottom of the pot. This step is very important to avoid getting the "BURN" message.
After the pot is deglazed and there are no more stuck bits off of the bottom of the pot, add seasoning or saffron, frozen vegetables, and cooked chicken. Mix to combine. Taste and add more salt and pepper if necessary. Bring to a boil. Press "cancel". Secure the lid to the Instant Pot. Close the pressure release valve. Select "manual", or "pressure cook", and adjust the cooking time to 8 minutes.
When the time is over, let the pressure release on its own for 5 minutes. Then, carefully turn the valve to "Venting," to release any extra pressure that might still be in there. Then remove the lid. Press "cancel".
Fluff arroz con pollo with a fork, garnish with fresh chopped cilantro, if desired, and serve hot.