Okay, so a hundred-plus years after Japan discovered loose, soupy British-style curry and thickened and adapted it for a rice-eating culture, guess what? Soup curry makes a comeback! This second coming, as it were, began in 1971 when a restaurant in cold, snowy Sapporo, on the northern main island of Hokkaido, whipped up a comforting, soupy “medicine curry,” loaded with spices and herbs. Twenty years later, another Sapporo joint, named Magic Spice, picked up this curry, but minus the medicinals. They dubbed it, simply, “soup curry” and the effect was indeed magical—before long this tasty curry spread and specialized soup curry restaurants began popping up all over the city. Lucky for us: this lighter curry, loaded with veggies and chicken, is an absolute delight. But soupy or not, you still eat it with rice.
Cut the eggplant and zucchini in half lengthwise, and slice the halves on an angle into about 3-inch-long pieces. Cut the red pepper in half lengthwise, and cut into 1-inch-thick lengthwise strips. Set the vegetables aside.
Heat the vegetable oil in a large saucepan over high heat. Add the onion, carrot, garlic, and ginger and cook, stirring constantly, for about 3 minutes, until the onion turns translucent. Add the chicken and cook, stirring constantly, until the meat turns white. Add the curry powder and cook, stirring constantly, for 1 minute. Add the torigara stock, salt, bay leaves, and Japanese chilies and stir to combine. When the liquid comes to a boil, reduce the heat to a simmer. Cook the curry for about 7 minutes, stirring occasionally. Remove any scum that appears on the surface.
While the curry is simmering, heat the olive oil in a large skillet over high heat. Add the eggplant, zucchini, and red pepper, and cook, stirring constantly, for about 2 minutes, until the vegetables soften. Remove from the heat.
Once the curry has cooked for 7 minutes, add the sautéed eggplant, zucchini, and red pepper, and stir to combine. Cook for about 5 minutes more, stirring occasionally, until the vegetables are cooked through. As the curry cooks, remove any scum or excess oil that appears on the surface. Serve in soup bowls, with steamed white rice on the side.