I've seen ahi tuna tartare prepared where it's mounded onto a plate. To give a more appealing look and some texture, I like serving ahi tuna tartare on little discs of fresh cucumber slices. It has a wonderful crunch and the cucumber adds a nice cool freshness that compliments the ahi tuna. When arranged on a platter, these look so elegant and perhaps too pretty to eat...
Ahi Tuna Tartare
recipe adapted from Ina Garten
3 3/4 pounds very fresh tuna steak
1 1/4 cups olive oil
5 limes, zest grated
1 cup freshly squeezed lime juice
2 1/2 teaspoons wasabi powder
2 1/2 tablespoons soy sauce
2 tablespoons hot red pepper sauce
2 1/2 tablespoons kosher salt
1 1/2 tablespoons freshly ground black pepper
1 1/4 cups minced scallions, white and green parts (12 scallions)
1 half each, thinly sliced fresh small orange and red bell pepper, seeds removed
5 ripe Hass avocados
1 1/2 tablespoons toasted sesame seeds, optional
Cut the tuna into 1/4-inch dice and place it in a very large bowl. In a separate bowl, combine the olive oil, lime zest, lime juice, wasabi, soy sauce, Tabasco sauce, salt, and pepper. Pour over the tuna, add the scallions and bell pepper mix well. Cut the avocados in half, remove the seed and peel. Cut the avocados into 1/4-inch dice. Carefully mix the avocado into the tuna mixture. Add the toasted sesame seeds, if using, and season to taste. Allow the mixture to sit in the refrigerator for at least 1 hour for the flavors to blend.
Meanwhile, using a peeler, remove strips of the skin lengthwise off the cucumber, alternating the look of light green cucumber flesh and dark green peel. Slice the cucumber into 1/2 inch slices and remove the inner seeds just enough to create a small bowl or indention. Carefully spoon the chilled ahi tuna tartare into the middle of each cucumber slice and serve.