1Heat the oil in a large skillet over medium-high heat. Add the chicken and cook until it turns color, about 5 minutes. Add the onion and garlic, and cook until the onion is translucent, about 4 minutes. Add ¾ cup of the water, the curry powder, sugar, salt, black pepper, cumin, and turmeric. Stir and cook for 2 minutes to let the flavors meld.
2In a small bowl, stir together the cornstarch and the remaining 3 tablespoons water, then add to the chicken mixture, stir, and simmer until thickened. You’ll know it’s ready when there’s no pooling liquid. Transfer the chicken mixture to a medium bowl and let cool. You will have about 1¾ cups of filling.