I have also made Fish Jun with this recipe.
Unlike standard bulgogi where beef is shaved thin, meat jun requires precise cuts measuring roughly three by four inches at a quarter-inch thickness. This substantial cut demands a full one-hour marinade window to let the soy and sesame penetrate the dense muscle fibers. Freezing the chuck roast for thirty minutes beforehand makes achieving these uniform dimensions significantly easier.
While beef chuck roast forms the traditional base, alternate proteins adapt well to this coating method. Sliced firm white fish or pork tenderloin can replace the beef entirely. Reduce the marinating time to fifteen minutes when using delicate seafood proteins to prevent the flesh from breaking down in the liquid.
Coating the marinated slices requires a dry flour layer followed by a complete egg wash. Shake off excess liquid before placing pieces into the hot oil. Maintain a medium frying temperature so the egg coating browns to a golden hue without burning before the interior proteins cook through.