Marinate the chicken according to our velvet chicken recipe (see Note 1). Set this aside while you prepare the other ingredients. Mix together the ingredients for the curry sauce: 2 teaspoons soy sauce, ½ tablespoon curry powder, 1 teaspoon cornstarch, 1 teaspoon sugar, ½ teaspoon cayenne, ¼ teaspoon salt, and 1 to 1 ½ cup chicken stock. Set aside.
Heat 1 tablespoon oil in a wok or sauté pan on medium-high heat. Spread the 8 ounces velvet chicken breast over the wok in a single layer. Sear for a minute or two until golden brown, then flip and sear the other side. The chicken pieces should release easily from the pan with a thin metal spatula.
Transfer the chicken to a plate. Don’t worry about the centre being undercooked, we’ll be heating it through later.
Return the wok to the heat and add 4 ounces onions. Cook for another minute or so until the edges start to look seared.
Add 3 cloves garlic, 1 inch fresh ginger, 4 ounces potatoes and 4 ounces carrots and stir briefly. Pour over the curry sauce mixture. Cover and bring to a boil.
Turn the heat down to medium-low and simmer for 10 to 15 minutes, or until the potatoes and carrots are softened to your liking. If the curry sauce is too thin, remove the lid and let it simmer until thickened; if the sauce is too thick, add a bit more water.
Return chicken to the wok in the last minute of cooking. Sprinkle with 1 diced scallion, and serve.