Place the parsley, cilantro, poblano chiles, chopped onion, and garlic into a food processor along with 1/2 cup of chicken stock. Blend until smooth.
Stir the green purée into the toasted rice and sauté for about 2 minutes. Then, add remaining chicken stock, bring to a boil, reduce heat to low, cover the pot. Simmer for 15-20 minutes.