Under the hot broiler, char the bell peppers and jalapenos to blacken the skins evenly. Place the peppers in a bowl and cover to cool. Wipe off the skins with a paper towel and seed the peppers.
Meanwhile, sprinkle the chicken with salt and pepper, and then dredge in flour. Heat a couple of tablespoons of oil in a pan over medium-high heat and add the chicken to brown on both sides. Remove to a plate and add a bit more oil if necessary. Add the garlic, onions, coriander, cumin and some salt and pepper. Cook to soften, stirring occasionally.
Add 1 cup of the stock with the peeled peppers to a food processor and pulse to puree the peppers. Add the puree to the cooked onions and slide the chicken back into the sauce to finish cooking.
Cool and store for a make-ahead meal. Reheat over medium heat, adding a little water or stock if the sauce is too thick.
To serve, prepare the rice pilaf. Melt the butter in a saucepot over medium heat. Toast the broken pasta pieces to brown, then add the rice and the remaining 2 cups stock, and bring to a boil. Cover the pot and cook 15 minutes. Remove the pot from the heat and let stand 5 minutes, then fluff the pilaf with a fork.