Begin by heating a large pot over medium heat. Add 2 tablespoons of vegetable oil. Once the oil is hot, sauté the sliced onions for about 5 minutes, until they become translucent and slightly golden. Stir frequently to prevent burning.

Add the minced garlic and grated ginger to the onions, cooking for another 1-2 minutes until fragrant. These ingredients form the base of the curry’s rich flavour.

Add the beef, chicken, or pork to the pot. Stir well and cook until the meat is browned on all sides, which will take about 5-6 minutes. This step locks in the meat's juices and intensifies the flavour of the curry.

Next, add the carrots and potatoes to the pot. Stir everything together, then pour in the 4 cups of water or chicken broth. Bring the mixture to a boil, then reduce the heat to low and simmer for 15-20 minutes, until the vegetables become tender.

Once the vegetables are soft, grate the apple directly into the pot (if using). This adds a subtle sweetness and balances the spiciness of the curry. Stir well to combine.

Break the curry roux blocks into smaller pieces and add them to the pot. Stir continuously until the roux has completely dissolved into the broth, forming a thick, smooth sauce. This will take about 3-4 minutes.

Let the curry simmer on low heat for another 10 minutes to allow the flavors to meld together. Stir occasionally to ensure the sauce doesn’t stick to the bottom. If the sauce becomes too thick, you can add a bit more water to reach the desired consistency.

Serve the curry over freshly cooked Japanese short-grain rice. Garnish with pickled ginger or fukujinzuke on the side for added texture and flavour contrast. Japanese curry rice is best enjoyed hot, with a rich, savoury sweet sauce coating the tender vegetables and meat.