Oven method: Remove the cooked chicken from its packaging and preheat the oven to 350°F (175°C).
Place the chicken in an oven-safe dish, lightly spritz or sprinkle a few drops of water over the meat, then cover the dish tightly with aluminum foil.
Heat in the oven for 10–15 minutes or until heated through; larger or bone-in pieces may need longer.
Stovetop frying method: Remove chicken from packaging and pour vegetable oil into a frying pan to a depth of about 1/4 inch; heat over medium until a drop of water causes the oil to sizzle.
Carefully add the chicken to the hot oil, leaving at least 1 inch between pieces, and cook 2–3 minutes per side until heated; transfer to a paper-towel-lined plate to drain.
Microwave method: Place chicken on a microwave-safe plate, cover with plastic wrap, and heat for 1 minute. Check and continue heating in 1-minute increments until hot throughout.