Rinse Japanese short-grain rice under cold water until water runs clear. Soak in fresh water for 30 minutes, then drain and transfer to a pot with water. Cook covered for 15 minutes, then let sit for 10 minutes before folding in rice vinegar, sugar, and salt.

Pound boneless chicken breasts (or pork loin) to uniform ½-inch thickness. Season with salt and pepper. Set up a breading station with flour, beaten eggs, and panko breadcrumbs. Coat meat first in flour, then egg, and finally panko.

Heat ½ inch of vegetable oil in a skillet over medium heat until shimmering (about 350°F). Fry breaded chicken or pork for 4-5 minutes on each side until golden brown. Transfer to a paper towel-lined plate.

Mix tonkatsu sauce, soy sauce, Worcestershire sauce, and ketchup in a small bowl to create a dipping sauce. Adjust flavors as needed.

To assemble, place seasoned rice in each bowl, slice katsu on top, drizzle sauce over, and garnish with cabbage, green onions, sesame seeds, and optional pickled ginger.