Season the pork chops with salt and pepper.
Dust with flour
Dredge in the egg
Coat with Panko crumbs
Cook in a thin layer of oil in a skillet over medium heat (about 5 minutes each side)
Let cool on a draining rack.
Slice into pieces
Meanwhile (or even do this first)
Put the soup stock into a pot and cook on medium heat
Add soy sauce, mirin and sugar to the soup and bring to a boil. Stop the heat once boiled.
To cook the Katsudon, pour one quarter of the soup into a small skillet and add one-quarter of the onion slices in the soup and simmer for a few minutes on medium heat.
Add one serving of the cut tonkatsu pieces to the pan and simmer on low heat for a few minutes.
Beat an egg in a bowl. Bring the soup to boil over medium heat and then pour the egg over the tonkatsu and onion.
Turn the heat down to low and put on a lid.
Turn off the heat. Serve the tonkatsu, egg, onion in a large rice bowl.
Pour 1/4th of the soup on over the top.
