Mash garlic and 1/2 teaspoon salt to a paste; rub chicken with garlic mixture.
Arrange chicken in shallow glass or plastic dish; sprinkle with lime juice
and onion. Cover and refrigerate, turning occasionally, at least 3 hours.
Remove chicken from marinade and pat dry.
Heat 1/4 inch oil in skillet until hot; decrease heat to medium.
Mix flour, 1 teaspoon salt and the chili powder; coat chicken with flour
mixture and place chicken in skillet skin sides down. Cover and cook 5 minutes;
uncover and cook 15 minutes, turn chicken. cover and cook 5 minutes longer;
uncover and cook until thickest pieces are done, 10 to 15 minutes longer.