About half an hour before cooking season the tuna steaks with half the lemon juice and the salt and pepper, massaging gently into the fish. Set aside.
Whisk the rest of the lemon juice with 5-6 tablespoons of extra virgin olive oil, salt and pepper and reserve,
When ready to cook wipe the fish dry and brush with oil. Sear or grill the tuna as in the recipe for Tuna with Chermoula.
While it is cooking toss the rocket with the remaining dressing and spread on individual plates. Place a spoonful of tapenade and another of Aioli beside the rocket ( or put in two separate bowls on the table).
As soon as the tuna is cooked lay it on top of the dressed rocket so that the leaves wilt in the heat of the tuna. Serve immediately with the two sauces.