Peel the carrot and onion. Slice the carrot into thin rounds. Finely chop the onion.

Heat a little oil in a saucepan. Add the carrot and onion. Sauté over high heat for 3-4 minutes, stirring occasionally.

Add 1 1/4 cups water (300 ml) and bring to a boil. Reduce heat and simmer for 15 minutes.

Add the Japanese curry roux, cut into pieces. Simmer for 5 minutes over low heat, stirring constantly.

Remove from heat and let cool to room temperature. Then refrigerate.

Peel the potatoes and cut them into cubes. Steam for 10 minutes.

Mash the potatoes until smooth.

Set out 3 shallow bowls: put cornstarch in the first, beaten egg in the second, and panko breadcrumbs in the third.

On a piece of plastic wrap, spread a tablespoon of mashed potatoes. Place a heaping teaspoon of curry mixture on top. Cover with a thin layer of mashed potatoes. Shape into a ball, making sure the curry is completely enclosed. Repeat until all the mashed potatoes and curry are used.

Pour vegetable oil into a wok. Heat over medium heat.

Roll a potato-curry ball in cornstarch, then dip in egg, and finally coat with panko breadcrumbs.

Using a slotted spoon, place the ball in the wok. Fry for about 5 minutes per side, until golden brown. Place the croquette on a plate lined with paper towels.

Repeat until all the croquettes are fried.

Serve with salad, cherry tomatoes, and tonkatsu sauce.