In a small bowl whisk together the vinegar, stevia, soy sauce, hoisin sauce, salt, pepper, and pepper flakes until the salt dissolves. Whisk in the canola and sesame oils. Set the dressing aside.
On a serving platter, arrange the Napa cabbage in a bed. Arrange the chicken, then the orange sections on top of the cabbage. Pour the dressing over the salad. Sprinkle on the scallions, almonds, and sesame seeds, if using. Just before serving, toss to combine the layers.