Start by seasoning the Wagyu beef. Use a teaspoon of sea salt and a pinch of black pepper. Allow it to sit for about 10 minutes at room temperature. This helps with flavor absorption.

In a bowl, mix together the mayonnaise, canola oil, Sriracha sauce, tamari, and a pinch of brown sugar. This will become your creamy sauce to drizzle on the tacos later. Stir until smooth, and set aside.

In a skillet over medium-high heat, add a drizzle of oil. Once hot, add the Wagyu beef. Cook for about 3-4 minutes on each side for medium-rare. Adjust the time based on your preferred doneness. Once cooked, let it rest for a few minutes before slicing it into thin strips.

While the beef is resting, warm the taco shells in the oven or on a skillet for a few minutes. This adds a lovely crunch. Once warmed, fill each shell with slices of the cooked Wagyu.

Top the Wagyu with diced red onion, radish slices, and a sprinkle of fresh cilantro. Squeeze fresh lime juice generously over each taco. Finally, drizzle the creamy sauce you prepared earlier.

Your Nobu Wagyu tacos are ready to be served! Present them on a colorful platter. Garnish with additional lime wedges on the side for that extra zest.