Frozen roast pork should be thawed in the refrigerator overnight. Place the piece of roast pork side down on a non-stick saucepan.
Heat up pork over a gentle low heat for 3 minutes for both meat and skin side. Use a fork to hold on to the meat, heat all the 4 sides of the meat for 2 minutes each side.
Finally, heat the piece of roast pork, meat side and skin side for 1 minute each again. This would enable the roast pork to have a crispy skin and the meat is sealed with moisture inside.