Take your block of Ahi Tuna and pat dry with a paper towel. Using a pepper mill, crack enough Whole Black Peppercorns to coat every edge of the fish. Lightly press it in to ensure it sticks. Sprinkle some salt on the fish.
In a very hot pan, add the Olive Oil, and a few seconds later add the fish.
I like to cook for about 1 minute on the first side, and just 30 seconds on the second to keep the middle perfect, but if you want it more cooked, that's entirely up to you.
Let cool and then slice about 1/2 cm thick slices. This can be served as is, or atop a light salad. If you would like a dipping sauce, I enjoy Ponzu sauce, which is basically equal parts Soy Sauce and Lemon Juice with a little bit of rice wine vinegar and Dashi.