Cut the pork slices crosswise into 1/6-inch (4 cm) strips.

In a medium heavy pot, heat the oils over medium heat until hot but not smoking. Slide in the pork or beef and stir-fry for I-2 minutes, then add the onion and cook, stirring, until the pork has browned and the onions are deeply golden, about 5 minutes. Stir in the ginger and garlic in the last minute or two before the pork and onions are done.

Add the broth and deglaze the pan. Bring to a boil over high heat, add the carrots, apple and potatoes, and cook until just cooked through, 5-7 minutes.

In a small bowl, blend the curry powder with a small amount of broth from the pot to make a slurry. Add that to the pot.

Add the potato starch mixture, mirin, and soy sauce and simmer until thickened, 7-10 minutes longer. Add any additional ingredient of choice here.

If the bottom of the pan is browning or sticking, adjust the heat to low. Serve hot on top of a bed of Japanese rice. The curry rice heats up well for leftovers over the course of several days.