Begin by pounding the chicken thighs to a uniform thickness of about ½ inch using a meat mallet. Season both sides with salt and pepper.

In a mixing bowl, whisk together the eggs, all-purpose flour, salt, and black pepper until the mixture is slightly looser than pancake batter.

Set up a breading station, placing the seasoned chicken in the batter followed by the panko breadcrumbs.

Heat neutral oil to 350°F. Fry the chicken for 4–6 minutes until golden brown. Transfer to a wire rack to cool.

Cook sushi rice and season it with rice vinegar, sugar, and salt once cooked.

Lay a nori sheet shiny side down, pack sushi rice into a mold, drizzle with tonkatsu sauce, and add a piece of crispy chicken.

Wrap the nori around the rice and chicken tightly. Use water on the edges to seal.

Slice the musubi into manageable pieces and arrange them on a plate.