Mix the marinade ingredients in a bowl and add the chicken, turning to coat. Cover and refrigerate for at least 1 hour.
Pre-heat the grill to high. Lift the chicken from the marinade and place on a baking tray. Grill for 8 minutes on each side or until cooked through. Remove from the heat and rest for 5 minutes before slicing.
Heat the oil in a large saucepan over a medium heat. Add the onion and cook, stirring occasionally, until translucent. Add the garlic, tomatoes and pimentos. Stir in the beans, rice, water, herbs, salt to taste and cayenne pepper. Bring to the boil, reduce the heat and simmer until all the water is absorbed, about 12 minutes.
Check the rice is thoroughly cooked. Ivied between plates and serve with the chicken, an extra sprinkle of coriander and a lime wedge on the side.