Step 1 - Prepare the Green Onions and Onion: Thinly slice 3 to 4 green onions. You can slice them straight across or on a diagonal. Set aside a small amount of the green onion for the final topping. Thinly slice the sweet Maui onion or red onion as well. Sweet Maui onion is a traditional choice for poke, but red onion works well and adds extra color to the finished dish.
Step 2 - Prepare the Fresh Ginger: Peel a small piece of fresh ginger and grate or finely mince it. The ginger adds another layer of flavor to the poke marinade, but you can leave it out if you do not enjoy its taste.
Step 3 - Prepare the Ahi Tuna: Use about 2 pounds of very fresh sushi-grade or sashimi-grade ahi tuna that is suitable for eating raw. Do not rinse the tuna under water. If there is excess moisture on the surface, gently blot it dry with a clean paper towel. Cut the tuna into cubes about 1 inch in size and transfer the cubes to a large mixing bowl.
Step 4 - Make the Poke Marinade: Pour 2 tablespoons of sesame oil and about 4 tablespoons of soy sauce over the cubed tuna. Add most of the sliced green onions, reserving a little for the topping. Add the thinly sliced sweet Maui onion or red onion, 1 to 2 tablespoons of sesame seeds, and the grated fresh ginger. Gently mix everything until the tuna is evenly coated with the soy sauce, sesame oil, onions, sesame seeds, and ginger.
Step 5 - Marinate the Ahi Poke: Cover the bowl and place the poke in the refrigerator for about 10 to 15 minutes. This gives the tuna time to absorb the flavors while you prepare the remaining ingredients and the crispy wonton chips.
Step 6 - Slice the Radishes: Wash the radishes and slice them very thinly. Radishes are optional, but they add a fresh crunch and a nice contrast to the soft ahi tuna and avocado. Set them aside until you are ready to assemble the nachos.
Step 7 - Cut the Avocado: Cut the avocado in half and remove the pit. Score the flesh into chunks while it is still inside the skin, then use a spoon to scoop the avocado pieces out. Chunked avocado works especially well for the nachos because it sits nicely among the poke and wonton chips.
Step 8 - Cut the Wonton Wrappers: Take the wonton wrappers and cut each one into triangles. These will become the crispy base for the poke nachos. Wonton chips are lighter than traditional tortilla chips and pair well with the fresh tuna.
Step 9 - Fry the Wonton Chips: Pour enough vegetable oil or peanut oil into a pan for frying and heat it. Fry the wonton triangles in batches, making sure not to overcrowd the pan. Cook them until they turn lightly golden brown, bubbly, and crispy. Remove the chips from the oil and place them on paper towels to absorb any excess oil. Continue until all of the wonton triangles are fried.
Step 10 - Arrange the Wonton Chips: Place the crispy wonton chips on a large serving plate or platter. Spread them out so there is enough surface area for the ahi poke and toppings.
Step 11 - Add the Marinated Ahi Poke: Remove the ahi poke from the refrigerator after the 10 to 15 minute marinating time. Spoon the marinated tuna over the crispy wonton chips, making sure the tuna is distributed across the plate.
Step 12 - Add the Fresh Toppings: Scatter the thinly sliced radishes over the ahi poke, then add the chunks of avocado. Sprinkle additional thinly sliced onion and the reserved green onions over the top. Add more sesame seeds for extra texture and flavor.
Step 13 - Finish and Serve: Serve the ahi poke nachos immediately while the wonton chips are still light and crispy. If you want extra flavor or heat, add cilantro, sliced jalapeños, or thinly sliced nori on top. The finished dish combines tender raw ahi tuna with soy and sesame flavor, creamy avocado, crisp radishes, fresh onions, and crunchy wonton chips.