• Charred tuna tataki (The Chefs' Line)Source: The Chefs' Line

There are a lot of hidden elements in this dish but you can’t see them on the plate. One of them is our signature carbonised leek aioli.






Skill level

Average: 3.8 (14 votes)


Tuna and leek ash powder

  • binchotan charcoal (see Note)
  • 65-70 g piece sashimi-grade tuna
  • 20 ml grapeseed oil, for brushing100 g leek, white part, big and thick


Shiitake sauce

  • 2 shiitake mushroom
  • 15 ml water
  • 30 g caster sugar
  • 30 ml soy sauce (see Note)
  • 2 tsp sesame oil
  • 10 ml mirin
  • 1 garlic clove
  • ½ tsp freshly ground black pepper
  • 10 g nashi pear juice


Pickled asparagus

  • ½ green asparagus spear
  • ½ white asparagus spear
  • 50 ml yuzu juice (see Note)


Pickled enoki

  • 30 g enoki mushroom
  • 36 ml white (light) soy sauce (see Note)
  • 80 ml grapeseed oil
  • 10 g lime juice


Smoked ponzu

  • 40 ml soy sauce (see Note)
  • 15 g A-grade bonito flakes (katsuobushi)
  • 60 ml rice vinegar (shiragiku)
  • 20 ml grapeseed oil


Pickled ginger gel

  • 50 g pickled ginger in juice


Micro herb garnish

  • 10 g micro green shiso leaves
  • 10 g micro red shiso leaves
  • 5 g micro mâche leaves
  • 5 g edible flower, colourful


Carbonised leek sauce base

  • 6 g carrot
  • 6 g onion
  • 1.5 ml sake
  • 1.5 ml soy sauce (see Note)
  • 1.5 ml mirin
  • 3ml rice vinegar (shiragiku)



  • 3 ml soy sauce (see Note)
  • 5 ml lemon juice


Carbonised leek sauce

  • 4 g white miso
  • 1 quantity ponzu (see above)
  • 1 garlic clove
  • 4 ml mirin
  • 4 ml soy sauce (see Note)
  • 1 quantity carbonised leek sauce base (see above)


Carbonised leek aioli

  • 100 g homemade mayonnaise
  • 1 quantity carbonised leek sauce (see above)          
  • leek ash powder, to taste (see above)
  • 2 g xanthan gum powder (see Note)

Cook's notes

Oven temperatures are for conventional; if using fan-forced (convection), reduce the temperature by 20˚C. | We use Australian tablespoons and cups: 1 teaspoon equals 5 ml; 1 tablespoon equals 20 ml; 1 cup equals 250 ml. | All herbs are fresh (unless specified) and cups are lightly packed. | All vegetables are medium size and peeled, unless specified. | All eggs are 55-60 g, unless specified.


For the tuna and leek ash powder (see Note), heat the charcoal to hot. Brush the tuna with grapeseed oil, season with salt and pepper, then use the charcoal to sear every side of the tuna. Refrigerate until chilled.

Trim the leek to about 5 cm long. Place it on a grillplate over the charcoal and grill all over until the outer layer is completely charred and burnt like ash. Use a knife to scrap off the leek ash into a mortar and pound to a fine powder. Set aside.

For the shiitake sauce, remove the mushroom stems and discard, cut the mushroom caps into four pieces.

In a blender, place the water, soy, sugar, sesame oil, mirin, garlic and black pepper and blend until smooth. Transfer to a small saucepan, add the mushroom, bring to the boil, then simmer and cook for 1 minute. Allow to cool to room temperature, then add the nashi juice. Set aside.

For the quick pickled asparagus, peel both the asparagus. Blanch only the green asparagus in salted boiling water for 30 seconds, then refresh in iced water until cool, drain and pat dry. Trim both green and white asparagus to about 4 cm long, then cut lengthways into four sticks each.

Just before serving, pickle in the yuzu juice for 1 minute.

For the pickled enoki, trim the enoki in half. Combine the soy, oil and lime juice in a bowl and mix until emulsified. Just before serving, pickle the enoki in the mixture for 5 minutes.

For the smoked ponzu, bring the soy to a simmer in a small saucepan, then remove from the heat, add the bonito flakes and stand for 10 minutes. Strain, discarding the bonito. Add the vinegar and oil and mix well.

Just before serving, marinate the seared tuna in the smoked ponzu for 5 minutes.

For the pickled ginger gel, blend the pickled ginger and enough juice together to reach a gel consistency. Set aside.

For the carbonised leek sauce base, in a blender, place the carrot, onion, sake, mirin, soy, and vinegar, and blend it until very smooth, then pour into a medium-size mixing bowl.

For the ponzu sauce, combine the ingredients.

For the carbonised leek sauce, in a blender, place the white miso, ponzu, garlic, mirin and soy, and blend it until smooth. Add the carbonised leek sauce base and blend until combined.

For the carbonised leek aioli, in a mixing bowl, combine the mayonnaise and carbonised leek sauce and mix very well. Spoon one-quarter of the mixture into a blender, add the leek ash powder and xanthan gum powder, and slowly blend until thickened, then add the remaining mixture and blend until it thickens to mayonnaise consistency.

To serve, spread the carbonised leek aioli in a 4 cm square in the centre of a plate and blowtorch the aioli to bring the flavour out.

Slice the tuna into 6 pieces and arrange on top of the aioli.

Arrange the shiitake, enoki, and asparagus around the tuna, fill the gap with herbs and flowers.

Place about 6 dots of ginger gel around the tuna, and drizzle the smoked ponzu on top of the tuna. 


Chef’s notes

• Binchotan charcoal is a clean-burning Japanese charcoal, which is available from Asian grocers and barbecue stores. If you don’t have a charcoal barbecue, you can sear the tuna in a hot pan or and char the leek over a gas flame.

• I like to use Yamasa brand soy sauce, and Higashimaru brand white (light) soy sauce, available from Japanese grocers.

• Xanthan gum can be ordered online or is available from specialty cooking stores.


Chase Kojima is the head chef of Sokyo and Gojima. This recipe is from The Chefs' Line - a brand new series airing weeknights at 6pm on SBS. Can the passion of a home cook beat the skills of a professional chef? Missed all the action? Catch-up online and get all the recipes #TheChefsLine.

This recipe has been edited by SBS Food and may differ slightly from the series.