Using a sharp knife, slice the tuna into 1/2-inch strips with the grain, then cut the strips into triangular pieces and place them in a mixing bowl. Puree the ginger with the sliced garlic in the bowl of a food processor. Scrape the sides of the bowl, add the soy sauce, and slowly pour the oil in with the machine running. Drizzle this mixture over the fish and gently toss to cool. Marinate the tuna for a minimum of 4 hours or overnight in the refrigerator. Preheat the oven to 400 degrees. In a bowl, combine the wasabi with a few drops of water, then add the minced garlic and mayonnaise. Add salt and pepper to taste and the green food coloring (if desired) to intensify the color of wasabi. Place the wasabi mayonnaise in a squeeze bottle if available. Remove the tuna from the marinade, place on a greased baking sheet, and bake it for 3 to 4 minutes, until the inside is pink. Or pan-sear in a hot skillet over medium heat for 2 to 3 minutes. Place the pieces of tuna on rice crackers, and top each with a little wasabi aioli. Sprinkle with black sesame seeds and diced red pepper.
Recipe courtesy of Pamela Morgan, President of Flavors Catering