1. In a large, deep frying pan, heat the oil over moderately high heat. Season the chicken with 1/4 teaspoon of the salt and the pepper and add to the pan. Cook, turning, until well browned, about 8 minutes in all. Remove. Pour off all but 1 tablespoon of the fat from the pan.
2. Add the onion to the pan and reduce the heat to moderately low. Cook, stirring occasionally, until translucent, about 5 minutes. Add the garlic and cook, stirring, for 30 seconds longer. Add the tomatoes and pimientos, scraping the bottom of the pan to dislodge any brown bits. Stir in the beans, rice, water, parsley, the remaining 1 1/2 teaspoons of salt, and the cayenne, and arrange the chicken on top in an even layer.
3. Bring to a boil and simmer until all the water is absorbed, about 12 minutes. Turn the drumsticks and reduce the heat to very low. Cover and cook until the chicken and rice are just done, about 15 minutes longer. Serve with the lime wedges, if using.
Wine Recommendation: A fruity red wine such as a merlot is best with this classic dish. If you can, try to find a bottle from a producer in Argentina or Chile, or open your favorite California merlot.