Prepare the Katsu Chicken: Slice each chicken breast horizontally to create two thinner cutlets. Place between two sheets of cling film and pound gently to an even thickness (about 1/2 inch).

Set up a dredging station: one shallow dish with flour, one with beaten eggs, and one with panko breadcrumbs. Season the flour with salt and pepper.

Dredge each chicken cutlet first in flour, shaking off excess, then dip in egg, and finally coat generously with panko breadcrumbs, pressing gently to adhere.

Heat vegetable oil in a large non-stick pan over medium heat. Fry the chicken cutlets for 4-5 minutes per side, until golden brown and cooked through. Remove and drain on paper towels. Keep warm.

Make the Katsu Curry Sauce: In a saucepan, sauté the chopped onion in a little oil over medium heat until softened, about 5-7 minutes.

Add minced garlic and grated ginger, cook for another minute until fragrant.

Stir in the curry powder and flour, cook for 1 minute, stirring constantly, to create a roux.

Gradually whisk in the hot chicken or vegetable stock until smooth and no lumps remain. Bring to a simmer, stirring occasionally, until the sauce thickens.

Stir in the soy sauce and honey/sugar. If using, add the coconut milk and stir until combined. Taste and adjust seasonings.

Assemble and Serve: Slice the cooked chicken katsu into strips. Serve immediately with sticky rice, a generous pour of the warm katsu curry sauce, and a sprinkle of sliced spring onions. Add pickled ginger if desired.