Combine 1 tablespoon of the vegetable oil with the butter in a medium pot over medium heat. When butter melts into the oil, add the 1/4 cup chopped onions and cook 2 minutes. Add rice and cook 3 minutes more. Add stock and cover the pot.
Bring to a rapid boil. Once stock is boiling, reduce heat to low and cook, stirring occasionally, until rice is tender (17 - 18 minutes).
While the rice cooks, heat a large skillet over high heat. Add remaining 2 tablespoons of oil, then the chicken. Season chicken with grill seasoning. Lightly brown chicken on both sides then move off to one side of the pan. Add the 3/4 cup thinly sliced onions, garlic, and bell peppers. Cook 2 - 3 minutes then mix the vegetables and meat together and add chipotles and cumin. Toss to coat.
Glaze mixture with honey and syrup and turn heat off. Add cilantro or parsley and nuts.