If they are thick, cut in half lengthwise. Cut diagonally into pieces about 1 inch long. Cook the carrots in boiling water for 3-5 minutes, depending how crunchy you like your carrots. Stir well and set aside. Heat 3 Tbsp of oil very hot in a wok or deep cast iron pan.
Peanut oil is best since it has a high smoking point.
Remove to a dish. Repeat until all the chicken has been cooked, adding small amounts of oil as it gets used up. Heat 1 Tbsp oil in an empty wok. Stir fry the parboiled carrots and the green pepper for 30 seconds. Add the chicken and the pineapple chunks to the vegetables in the wok.