Combine the lime zest and all the other ingredients up to and including the salt, brush the salmon with the marinade, place in the dish. Coat with the remaining marinade. Cover the dish with foil.
Cook in the oven
Cook the salmon in the covered dish at 160 C for approx. 20 mins. Remove the fish, pull apart using two forks.
Pour the sesame seeds into a deep bowl and roll the avocado halves in the them. Top 4 avocado halves with salmon, lettuce, cucumber and cress. Place the remaining 4 avocado halves on top, press down lightly.