In a large skillet, heat the vegetable oil until shimmering. Add the prepared vegetables and saute until crisp-tender, a couple minutes. Season with salt and pepper. In a bowl, serve up a large scoop of Rumbi rice, a scoop of hot vegetables, a scoop of grilled chicken cubes, and a heavy drizzle of Spicy Hawaiian Teriyaki sauce.
To make the rice: Combine the water, coconut milk, and sugar in a large saucepan. Stir in rice and beans. Bring to a boil over medium heat. Cover, reduce heat, and simmer 18 to 20 minutes, until rice is tender. Fluff with a fork before serving.
To make the Spicy Hawaiian Teriyaki Sauce: Combine the bottled teriyaki sauce, soy sauce, Sriracha, ginger, salt and brown sugar in a small saucepan. Bring to a boil and then reduce to a simmer. Combine cornstarch and water and SLOWLY add as needed for thickening (you may not need all of it.) It should be slightly syrupy; allow to simmer and thicken, about a minute. Serve warm over your rice bowls. (If you find that the sauce is too thick when it cools, just add a little more teriyaki sauce to it.).