Make deep cuts in the top of the lamb leg. Put lamb in a glass or ceramic dish.
Place the coriander leaves and stems, mint leaves, garlic, lime rind, lime juice, sesame oil, fish sauce and sesame seeds in a small food processor. Process until finely crushed. Rub the mixture over the lamb. Cover. Refrigerate overnight.
Preheat a Weber, enclosed barbeque or oven to 180°C. Place the lamb in a foil tray and cook for 1 1/2-2 hours. Cover with foil and set aside for 10 minutes before slicing. Serve with barbequed vegetables.
Notes & tips
Note: Add a selection of vegetables such as red onion, chat potatoes, pumpkin wedges and zucchini pieces to the foil tray. Drizzle with a little olive oil and cook with the lamb.