Very simple, but delicious. First, get good sashimi/sushi grade tuna that is safe to eat raw.
Rub it with some sesame oil, then coat it with black and white sesame seeds. Sear it in a little olive oil on both sides until it's seared on the outside and rare in the middle. That's pretty much it. Swipe it in some wasabi, dip it in the sauce, and eat a piece of pickled ginger between slices.
Dipping sauce is soy sauce, sesame oil, brown sugar, grated ginger root, grated garlic, red pepper flakes, and finely-chopped green onions, and whatever else I take a notion to throw in there. Make the sauce up ahead and let it sit awhile for the flavors to marry.
