1.Combine butter, chilli, pepper, rind and rosemary in a small bowl.
2.Rinse chicken under cold water; pat dry with absorbent paper. Cut along each side of chicken’s backbone; discard backbone. Turn chicken skin-side up; press down to breastbone with the heel of your hand to flatten. Using your fingers, carefully loosen and lift the chicken skin. Push butter mixture between the skin and flesh
3.Heat a covered barbecue. Place chicken in a disposable aluminium barbecue dish or baking dish; cook chicken in covered barbecue, using indirect heat, following manufacturer’s instructions, over low heat for 1 hour 20 minutes or until browned all over and cooked through.
4.Meanwhile, combine remaining ingredients in a small bowl.
5.Remove chicken from dish; strain juices from dish into a small heatproof jug. Return chicken to dish; sprinkle with crumb mixture, drizzle ¼ cup of the juices over the crumb mixture
6.Cook chicken in covered barbecue, using indirect heat, following manufacturer’s instructions, over medium heat for further 5 minutes or until topping is browned lightly. Cut chicken into quarters to serve