Heat oil in a medium Dutch oven over medium heat. Add onion and celery, and cook until soft and translucent, 10 minutes. Add garlic, and cook until soft, 2 minutes. Add chicken, orange juice, vinegar, currants, sugar, and peperoncini. Bring to a simmer; cover, and cook until chicken is cooked through, 20 minutes. Cut each piece in half.
Meanwhile, bring a pot of water to a boil. Add couscous, and cook until al dente. Drain. Serve chicken with sauce over couscous.
You could sub out the "Israeli" couscous for hulled barley, brown rice or quinoa.
LOOOOOOL "Israeli" couscous.