In a small bowl, add the lemon zest, dill and olive oil and combine well. Rub the tuna with the mixture and marinate, covered, in the refrigerator for 1 hour.
Preheat oven to 450 degrees F.
Place 2 cups of the salt on a baking tray. Lay 1 side of the tuna in the salt and place in a very high oven or on a grill and bake for 15 to 20 minutes for medium-rare to medium, or longer if desired. All sides should be seared and the inside of tuna should be rare.
2009, Robert Irvine, All Rights Reserved
Recipe courtesy of Emeril Lagasse