The true bluefin sauté is a dish from the live action One Piece adaptation. Being a work of fiction some ingredients were made up, like the elephant tuna, which I can assume would be equivalent to just a high quality piece of tuna. The rest of the description is quite vague, sweet soy reduction, seared asparagus, and a red tulie. Now you do see sautéed onions and a brief glimpse of what could be basil used to make a green oil. However I decided to take creative liberties and remove the basil (if it was basil) and replace it with parsley and chives in the green oil.

General ingredients

• 500 grams / 1 lb tuna, preferably the top loin. Or top part of the fish, not the belly.
• Asparagus spears
• toasted sesame seeds

Sweet soy reduction

• 237 ml soy sauce
• 100 grams light brown sugar
• 5 black peppercorns
• 5 Szechuan peppercorns
• 5 coriander seeds
• 1 clove
• 1 star anise pod
• 1 1″ knob ginger- sliced
• 1 clove garlic- smashed

1. Simply combine all ingredients in a medium saucepan and place on the stove over medium heat.
2. Bring it to a simmer and continue to cook until it becomes thick enough to coat a spoon, around 15 minutes. It will thicken up more as it cools also.
3. Strain and reserve.

Togarashi tuile

• 200 ml water
• 20 grams all purpose flour
• 5 grams togarashi
• 5 grams sunflower oil
• 5 drops red food dye (optional)

1. Grab your scale and set up a small bowl on top. Tare or clear the weight.
2. Measure your dry ingredients, then add your wet ones. Stir to combine. It’s a very loose, watery batter.
3. Preheat a small non stick pan over medium high heat. Add a small amount of a neutral oil, once it begins to shimmer and you see small wisps of smoke add 2 oz/60ml of your tuile batter or just enough to coat the bottom without going up the sides at all. Best way to keep it consistent is to use a 2oz/60ml ladle. It’s going to splatter a lot as the water evaporates so be prepared for that. But continue to cook until all the water evaporates and you’re left with a crispy tuile. This usually takes 3-4 minutes.
4. Remove the tuile from the pan and place on a paper towel lined tray to drain. Season with salt and reserve.

Green oil

• 175 ml sunflower oil
• 15 grams parsley
• 10 grams chives

1. Bring a pot of water to a rolling boil and have a bowl of ice water nearby.
2. Drop your parsley and chives into the boiling water for 15 seconds then pull it out and plunge into the ice water.
3. Once the herbs are cold squeeze out as much water as you can.
4. Place the herbs and the oil into a blender and blend for 3-4 minutes.
5. strain through a fine mesh strainer lined with cheesecloth. Let this strain for an hour or so. Discard the solids and reserve the green oil.

Dashi braised onions

• two medium sized yellow onions (around 350g)
• 475 ml water
• 1 sheet kombu
• 13 grams bonito flakes
• sweet soy reduction (from above)

1. To make the dashi, add the kombu and water to a pot and bring to a boil. Once at a boil add the bonito flakes and turn off the heat. Allow this to steep for 30 minutes before straining. Reserve.
2. Small dice your onions. Preheat a sauté pan over medium high heat and add a bit of neutral oil. Once the oil shimmers and you see wisps of smoke add the onions and a small pinch of salt. Sauté stirring or tossing constantly. We want to get even color on all these onions without them burning. After about 4 minutes add around an ounce/30 ml of dashi. Once the pan is completely dry and you see some fond (browning) forming on the bottom of your pan again, add another round of dashi. Repeat this process until the onions have softened but are not mushy, and are a nice deep golden brown- this took me around 15 minutes.
3. Once you’re happy with the color of your onions add in enough sweet soy reduction to coat, and you can just do this step to taste.

Finishing the dish

1. Pull your tuna out of the fridge a couple hours before cooking. We’re going to sear the outside and leave it mostly raw but you still want it warmed through.
2. Trim up your asparagus by removing the woody ends of the stem.
3. By this point you should have your onions cooked, warm, seasoned and ready to go. Your tuiles should be ready. Your oil should be finished straining. And have your sweet soy reduction ready as well.
4. Preheat a pan over medium heat and add some neutral oil, once it shimmers and smokes add the asparagus, a piece of smashed garlic, and a pinch of salt. Gently rock the pan back and forth to keep the asparagus constantly moving, you want to blister the outside without getting any hard sears. To check for doneness poke it with a fork and it should be just barely tender. This took me around 4 minutes. Remove from the pan with the garlic and give the pan a wipe with a towel.
5. Add some fresh oil to the same pan and season your tuna with salt. Sear your tuna on all sides- best way to get an even sear is to set a timer or just count in your head for each side. Drop it in and count to twenty and turn it. Once seared on all sides remove it from the pan and lightly pat with a towel to remove excess oil and brush on some of the sweet soy reduction.
6. To plate add a small bed of the braised onions, top with a pinch of sesame seeds. Add two pieces of sliced seared tuna on top. Arrange your asparagus next to the tuna, drizzle the green oil around the fish. And lastly add a piece of tuile. Serve