1.Place burghul in small bowl, cover with the boiling water, stand 10 minutes or until burghul softens and water is absorbed.
2.Combine burghul in medium bowl with lamb, onion, zucchini, mint and egg. Shape mixture into four patties.
3.Heat oil in large frying pan, cook patties, over medium heat, until browned both sides and cooked through.
4.Meanwhile, preheat grill (broiler).
5.Split rolls in half, toast cut sides. Sandwich lettuce, patties, tomato and hummus between roll halves.
To freeze. Complete recipe to the end of step 2. Individually wrap patties in plastic wrap. Label, date and freeze for up to three months. Thaw overnight in the refrigerator. Continue from step 3.