Place cubed potatoes in a small pot of boiling water High for 5-10 minutes.
Heat oil in a large skillet over medium heat. Place chicken in oil and cook to brown. Then stir in green peppers and onions; cook about 4 minutes. Stir in potato, coconut milk, curry sauce, salt, and 3/4 cup water.
Mix together cornstarch and 1/4 cup water. Stir into skillet, and simmer 10 minutes.