Mix together sugar, salt, sesame oil, dark soy sauce, and light soy sauce to create the marinade.

Cut the pork loin into strips approximately 2"x2" and 6" long.

Add the pork strips to the marinade in a plastic bag.

Refrigerate the pork in the marinade for 24 hours.

Prepare a grill for indirect heat using charcoal, arranging the coals around a drip pan.

Place the marinated pork on racks over the indirect heat.

Baste the pork frequently with the marinade.

Grill until the meat is firm and well done.

Be careful to avoid burning the pork due to the high sugar content of the marinade.

Once cooked, slice the cha siew pork thinly or chop it for use in your desired recipes.