Cut potatoes into bite-sized pieces, soak in water for 5 minutes, then drain. Microwave in a heatproof container covered with plastic wrap at 600W for 6 minutes. Mash the potatoes in a bowl and let cool.

Mince the onion and microwave in a heatproof container covered with plastic wrap at 600W for 1.5 minutes.

Mix mashed potatoes, microwaved onion, and corn in a bowl. Add mayonnaise, vinegar, and salt and pepper, then mix well. Shape the potato salad into bite-sized balls using plastic wrap.

Lay out pork slices, sprinkle with salt and pepper, and coat with cornstarch.

Wrap each potato salad ball with a pork slice.

Heat cooking oil in a frying pan and cook the wrapped potato salad balls until browned.