Cut one onion into very thin slices (thin enough to be translucent). Take out a mixing bowl and soak the pieces in cold water to get rid of the harshness.
Make dipping sauce: Mix Soy Sauce (3T), Honey (1T), Sugar (1T), Mirim (1T), Vinegar (1T). Then sprinkle a few shakes of sesame seeds, diced spring onion and diced chili peppers.
Butterfly your chunk of pork loin into thinner piece (reference video). Then cut the large pork slice in half. Now, use the back of your knife (or a tenderizer) and tenderize the meat. If you want a thicker piece, don't pound away too much.
Season the pork piece with salt & pepper - on both sides.