In a small saucepan over medium heat add in Water (1/4 cup), Caster Sugar (1 teaspoon), Fresh Ginger (1 teaspoon) and Red Chili Pepper (1 teaspoon). Bring it to a boil then lower the heat, stir it and leave it for 6-7 minutes.
For the Tonkatsu Sauce, in a bowl add Ketchup (1/4 cup), Soy Sauce (1 tablespoon), Worcestershire Sauce (1 tablespoon) and Lemon Juice (1 teaspoon). Mix until well combined and set aside.
Combine the Carrot (to taste), Green Cabbage (to taste), and Spring Onion (to taste) in a bowl and set aside.
To make the burger patties in a bowl combine the Lean Ground Beef (200 gram) and mix in about half of the Tonkatsu Sauce. Shape the patties and cook over medium-high heat for about 4 minutes on each side.
Rest for at least 4 minutes.
Toast the Hamburger Bun (2).
Drain the liquid and keep the Ginger and Chili.
To assemble, place Mayonnaise (1/4 cup) on bottom bun, salad slaw, burger patty, chili-ginger and finish with the remaining Tonkatsu Sauce. Serve and enjoy!