1. For the marinade*, combine the rice vinegar, olive oil, lemon juice, Kikkoman Roasted Garlic Marinade & Stir Sauce, ginger, onion and chilli flakes and mix to combine.
2. Place lamb in a large, flat non-metallic dish and pour over the marinade, turning to coat. Cover with plastic wrap and place in refrigerator for 2 hours** to marinate, turning once.
3. Pre-heat barbecue grill on moderately high heat. Remove lamb from refrigerator and pat dry with paper towels to help prevent burning. Reserve marinade.
4. Barbecue lamb for 10-12 minutes each side, or until cooked to your liking, basting from time to time with the reserved marinade.
5. Transfer meat to a carving board and allow it to rest for 15 minutes before slicing.
6. Place half a cup of Roasted Garlic Marinade in a small jug and serve separately.

Note: The sweet and sour salsa can be made the day before, stored in the refrigerator, then gently heated when needed.
* Tip: marinade can be made the day before and refrigerated until needed.
**Tip: marinate lamb for 4-6 hours or overnight in refrigerator for a deeper flavour.