Barbecued soy and ginger lamb recipe

Ingredients

• 1.5 kilogram butterflied leg of lamb, trimmed
• 3/4 cup (180ml) japanese soy sauce
• 1/2 cup (110g) firmly packed brown sugar
• 2 tablespoon olive oil
• 45 gram fresh ginger (45g), grated
• 6 clove garlic, crushed
• 1/3 cup (80ml) water
• Coriander potatoes
• 750 gram baby new potatoes, quartered
• 1 tablespoon olive oil
• 2 tablespoon finely chopped fresh coriander