Start by rinsing the uncooked parboiled rice under cold water. This helps remove excess starch and prevents the rice from becoming gummy.
In a medium saucepan, combine 4 ½ cups of water with ¼ cup of chicken stock base. Bring it to a boil over medium heat.
Once the broth is boiling, add the rinsed rice to the saucepan. Stir gently and reduce the heat to low. Cover the saucepan with a tight-fitting lid and let it simmer for about 15-20 minutes or until the rice is tender and has absorbed all the liquid.
While the rice is cooking, melt 4 tablespoons of unsalted butter in a skillet over medium heat. Add the diced green and red bell peppers and sauté them until they are softened, about 5 minutes.
Once the rice is cooked, fluff it with a fork and gently mix in the sautéed bell peppers and chopped cilantro. Stir until everything is well combined.
Transfer the Cilantro Rice to a serving dish, garnish with additional cilantro if desired, and serve warm.