Today’s sashimi tuna is served in quite a different way. The sashimi is sealed with boiling water first, then marinated in soy sauce flavour before slicing. With a white trim around each slice, and semi-transparent dark red meat in the centre, Marinated Sashimi Tuna looks very attractive. It is also tasty without dipping soy sauce.
This is a perfect sashimi to impress people. Look at the way the slices reflect the light, making it look almost semi-transparent! Every slice looks like that when you lift it up and see it through the light. So pretty.
Unlike standard sashimi, you don’t serve today’s tuna sashimi with soy sauce and wasabi. The block of tuna is marinated in a soy sauce flavoured marinade, making the thin layer of the flavoured flesh around each slice just right to eat.
The steps to make Marinated Sashimi Tuna
There are only three steps to make Marinated Sashimi Tuna:
Step 1: Seal the surface of a tuna block with boiling water – scalding.
Step 2: Chill the scalded tuna in ice water immediately. This is to prevent the tuna from cooking further.
Step 3: Marinate the chilled tuna block in the dashi and soy-based marinade for overnight, up to 3 days.
Extra Care to Scald Tuna
Scaled tuna resembles seared tuna but the thickness of the cooked area is much thinner.
Before pouring boiling water to seal the surface of a tuna, I cover the tuna block with a thin kitchen towel instead of directly pouring boiling water over the flesh.
By indirectly scalding the tuna, the surface of the tuna is cooked lightly, creating a very thin, elegant white trim around the meat when sliced.
It’s OK to seal the tuna without a kitchen towel but you will probably find that the surface of the sealed tuna is much whiter and the white trimming is thicker when sliced.
You will only need to change the colour of the surface to slightly white (see the step-by-step photo above). Gently pour boiling water evenly over the surface of the tuna block. Turn it over and scald on the other side. Do not forget to seal the side of the block, too.
The marinade is a mixture of konbu dashi and soy sauce with a tiny amount of sake. Some recipes marinate tuna in just soy sauce with a bit of mirin/sake. But I think that marinade with dashi added to the soy sauce gives a more subtle flavour to the marinated tuna.
In my recipe, I made the marinade from scratch starting by making konbu dashi. But konbu dashi can be pre-made the day before if you like.
Marinating time can be any time from overnight to 3 days. Even if you marinate for 3 days, the tuna does not become too salty.
You might wonder why and the secret is scalding. Because the surface of a block of tuna is sealed, the marinade cannot easily get through to the inside of the tuna.
When you slice the marinated tuna, you will notice that only the thin outer part of the tuna slice is slightly dark due to marinade.
Sashimi Tuna Block
It would be best if you can buy one rectangular sashimi tuna block like the one in my recipe. The size of the block I used was about 7cm x 14cm x 2.5cm/2¾” x 5½” x 1”. It was sold frozen at a Japanese grocery store.
If your sashimi tuna block is a different shape, e.g. triangle, cut the block into 2-3 rectangular blocks. It does not have to be a neat rectangle either, so try to make large blocks, thinking the size of a single piece when sliced.
Unlike usual sashimi, you have to spend some time on tuna before serving. But I must say it is worth the effort. It is a great appetiser or a side dish. It can even be served as a main.
PS: I added a new section ‘MEAL IDEAS’ below the recipe card. It gives you a list of dishes that I have already posted and the new recipe in this post that can make up a complete meal. I hope it is of help to you!
This is quite a different way of serving sashimi. The sashimi is seared with boiling water first, then marinated in soy sauce flavour before slicing. With a white trim around each slice and semi-transparent dark red meat in the centre, Marinated Sashimi Tuna looks very attractive. Great for serving at gatherings, too.
Sashimi can be served as side, appetiser or even main. Just change the serving amount per person.
Total Time does not include the time to marinate.
- 250g/0.6lb block of sashimi tuna (note 1)
- A thin kitchen towel
- Boiling water
- Ice water in a large bowl
- 200ml/8.5oz water soaked with 5cm x 5cm/2" x 2" konbu (note 2)
- 60ml/2oz soy sauce
- 1 tsp sake
- 4 perilla leaves
- finely chopped shallots/scallions
Add water with konbu in a small pot/saucepan and bring it to a boil.
Add soy sauce and sake to the pot. As soon as it starts boiling, turn the heat off and cool it down to at least room temperature, preferably even cooler. (note 3)
Place the tuna block in the centre of a cutting board and cover the tuna with a kitchen towel.
Place the cutting board with tuna on it in the sink, lifting one end higher to tilt the board.
Pour boiling water over it gently to sear the surface of the tuna. Make sure that the side of the tuna is also seared. Do not sear too much. As soon as the surface becomes white, that is sufficient (see the photo in blog).
Remove the kitchen towel, turn the tuna over and sear the surface in the same way.
Transfer the tuna to the ice water to cool it down quickly.
Pat the tuna dry with paper towel and place it in a container that just fits the tuna (note 4).
Add the marinade to the container and ensure that the entire tuna block is submerged in the marinade (note 5). Cover the container with a lid/cling wrap and marinate for at least overnight up to 3 days (note 6) in the fridge.
Remove the tuna block from the marinade and slice it into 7mm/¼" thick portions. Serve sliced tuna on perilla leaves by shifting each slice slightly to spread them and sprinkle chopped shallots over the sashimi if using.
1. Luckily, I could buy a neat rectangular shape of frozen sashimi tuna at the Japanese grocery store as you can see in the post. The size of the block was about 7cm x 14cm x 2.5cm/2¾” x 5½” x 1”. One block like this would be the easiest to handle.
But if your tuna comes in a different shape or in two smaller pieces, that’s quite alright, too. The important thing here is that the shape of the tuna block is suitable to make sliced sashimi.
2. Please refer to Varieties of Dashi Stock where the recipe for how to make Konbu Dashi is included.
3. If you want, you can make the marinade the day before.
4. You can also marinate tuna in a zip lock bag. But you need to turn the bag over occasionally while marinating so that the tuna is marinated evenly.
5. If your container is a bit too large and the tuna block cannot submerge in the marinade, place small shot glasses, bottles, baking beads, etc. around the tuna to increase the depth of the marinade. Of course, you can increase the amount of marinade as an alternative.
6. Searing the surface of the tuna prevents the marinade from penetrating into the flesh of the tuna too much. So, you can keep marinating for 2-3 days without making the tuna too salty.
7. Nutrition per serving as a side. I assumed 50% of marinating liquid would be consumed. Hence, the amount of sodium is very high. In reality, not much salt is absorbed into the tuna and sodium should be much less.
serving: 133g calories: 74kcal fat: 0.4g (1%) saturated fat: 0.1g (1%) trans fat: 0g polyunsaturated fat: 0.1g monounsaturated fat: 0.1g cholesterol: 24mg (8%) sodium: 481mg (20%) potassium: 313mg (9%) carbohydrates: 0.7g (9%) dietary fibre: 0.1g (0%) sugar: 0.1g protein: 16g vitamin a: 0.8% vitamin c: 0.1% calcium: 0.9 % iron: 3.7 %