For Japanese Mustard Mayo

1. In a small bowl, add 2 tbsp Japanese mayonnaise, 1 tsp Japanese mustard, 1/2 tsp sugar and 1 pinch of black pepper. Mix well and set aside for later.
   

For Miso Sauce

1. If you're making miso sauce as well or instead then take a small pan. Add 1 tbsp red miso paste, 1 tbsp honey, 1 tbsp sake, 1 tbsp mirin and 1 tbsp white sesame seeds.
   
2. Turn on the heat (low) and stir continuously.
3. Once thickened turn off the heat and set aside for later.
   

Fry the Katsu

1. You can start heating your oil straight away. Using a deep pan or fryer, you want to heat the oil to 170°C (340°F).
2. Next, prepare the katsu coating stations. In a dish, whisk one egg and prepare two separate plates, one with flour and one with the panko breadcrumbs. Three stations in total.
3. First, coat the pork chops with flour on both sides.
   
4. Next, dip them into the whisked egg.
   
5. Then, press them into the panko breadcrumbs, make sure it's fully covered.
   
6. Check your oil is hot enough, either with a thermometer or drop a piece of panko in. If the crumb sizzles and floats, you're ready to go!
7. Carefully place the coated pork chops into the oil and cook for about 4 minutes on each side (8 minutes total) or until golden brown.
   
8. While the katsu is cooking, finely shred your cabbage (as fine as you can!) and cut the crusts off of your bread pieces. (Cutting the crusts is an optional step but katsu sando you see in Japan nearly always has crusts cut off!)
9. When the oil stops making a crackling sound, that means the tonkatsu are ready. Set on a wire rack to let any excess oil drain off.
   

Assembling Japanese Mustard Mayo Katsu Sando

1. First, take a dish and pour in 1 tbsp worth of Worcestershire sauce.
2. Place your katsu into the Worcestershire sauce and let it absorb into the surface, do this on both sides.
   
3. Butter the bread and then add the mustard mayo.
   
4. Place the katsu on the bread and then spread more mustard mayo on the surface of the katsu.
   
5. Add the shredded cabbage and the last piece of bread. Press down firmly.
   
6. Cut off the ends where the katsu might be sticking out (you can eat these bits) and then cut the sandwich into halves or thirds.
   
7. Turn the katsu so the cut edge is facing up.

Assembling Miso Katsu Sando

1. Butter the bread and then spread a layer of miso on one piece.
2. Add shredded cabbage and the katsu on top.
   
3. Spread the miso sauce on one side (or both sides for extra flavour) of your katsu.
   
4. Top the katsu with another layer of cabbage.
   
5. Place the next piece of bread on top of the cabbage and press it down.
6. Cut the ends of the katsu if they're poking out of the sandwich.
   
7. Cut into halves or thirds and serve.
   
8. Enjoy!