1) Slice peppers and onions in wedges.
2) Thread zucchini, peppers, onions, mushrooms and tofu on to skewers with the vegetables alternating with tofu.
3) In a shallow baking dish, place the kebabs and pour over barbecue sauce keeping aside to marinate for 3 hours.
4) Over a hot grill, brown the kebabs lightly, basting with the marinade.
5) Serve with a rice pilaf after basting one more time with the marinade.