Pound pork cutlets (900 g) to an even 1/4-inch thickness. Season with salt and pepper.

Set up a dredging station with flour, beaten eggs (2 large), and panko breadcrumbs (4 cups) in separate shallow dishes.

Dredge each cutlet in flour, then dip in beaten eggs (2 large), and finally coat thoroughly with panko breadcrumbs (4 cups). Press gently to ensure the panko adheres.

Heat vegetable oil (4 cups) in a large, deep skillet or pot to 350°F (175°C).

Carefully place the breaded cutlets in the hot oil, ensuring not to overcrowd the pan. Fry for 3-4 minutes per side, or until golden brown and cooked through.

Remove the fried cutlets from the oil and place them on a wire rack to drain excess oil.

In a large pot or Dutch oven, sauté diced onion (1 medium), potatoes (2 medium), and carrots (2 medium) over medium heat until softened, about 5-7 minutes.

Add water (4 cups) and soy sauce (2 tbsp) to the pot and bring to a boil. Reduce heat and simmer for 10-15 minutes, or until the vegetables are tender.

Reduce heat to low and add the Japanese curry roux (8 oz) to the pot. Stir until the roux is completely dissolved and the curry sauce has thickened.

Simmer the curry sauce for another 5-10 minutes, stirring occasionally, to allow the flavors to meld together.

Slice the katsu cutlets into 1-inch thick strips.

Serve the sliced katsu cutlets over a bed of steamed rice and ladle generously with the Japanese curry sauce. Garnish with chopped green onions, if desired.