Roasted Seaweed Soup (Nori Sui) is a clear soup with torn roasted seaweed and very finely julienned ginger (harishōga). This is perhaps the simplest clear soup of all, but it is a luxury that uses an abundance of high-quality roasted seaweed (yaki nori, 焼き海苔). The elegant flavour of the broth comes from good dashi stock.
Today’s clear soup is called ‘nori sui’ (海苔吸い) in Japanese, which is the shortened name of ‘nori no osuimono’ (海苔のお吸い物) which means clear soup with roasted seaweed. The shortened name is not only easier and faster to say, but also sounds like a word used by a food connoisseur with a real flair. So, I like to call it Nori Sui.
When you sip Nori Sui, you are meant to taste a good flavour of seaweed with a sharp ginger taste. At the same time, you enjoy the delicately flavoured good broth. Because Nori Sui is made with only a few ingredients, it is critical to use quality ingredients and prepare them well.
What’s in my Roasted Seaweed Soup (Nori Sui)
It is a clear soup, so the broth is made using a standard set of ingredients for a clear soup. The ingredient in the clear soup is just roasted seaweed sheets, with harishōga as a garnish.
- Dashi stock
- Light soy sauce
- Cooking sake
You will need 1½ standard sheets of yaki nori per serving. The standard size of yaki nori is 21cm x 19cm/8¼” x 7½”, which is consistent across Japan.
The quality of yaki nori sheet is very important for today’s dish. So, I briefed about it in the following section.
Instead of harishōga, you can have roasted white sesame seeds, chopped mistusba, or chopped green onions. But I like the flavour contrast between the nori and ginger.
Just like quality nori sheets that are used for today’s soup, it is also important to use a good ichiban dashi, which is freshly made with konbu and bonito flakes. My post, Varieties of Dashi Stock explains how to make AWASE-DASHI, ICHIBAN-DASHI.
If you are a vegetarian, you can use konbu dashi, which is also explained in this post.
About Good Roasted Seaweed Sheets (Yaki Nori)
Some yaki nori are almost black, some are greenish, and some even come with a touch of reddish colour in the black.
The pigment of nori consists of green, red, bluish purple, and orange. By combining them together, it becomes black. The colour variation of yaki nori comes from the different balances between these colours in the nori.
When you grill or roast a seaweed sheet over fire, the black colour of the yaki nori turns greenish. This is because the red and blue colours are easily affected by heat, and the green and orange colours become dominant.
However, high-quality yaki nori contains a well-balanced large number of pigments so that it does not easily turn the colour of the nori sheet to green when heated.
Yaki nori is also sensitive to moisture. When the nori sheet becomes stale, it changes the colour to reddish purple. This is because the green pigment is weak against moisture.
It is said that a good roasted seaweed sheet is almost black. The next rank is blueish purple, followed by greenish sheets. In addition to that, the smooth side of the sheet should be shiny.
The best quality yaki nori comes from Ariake sea (有明海) in Saga prefecture. You can see the Kanji character for Ariake sea in the right nori pack in the above photo.
Rare Yaki Nori – Hatsutsumi
You might see the Japanese word, 初摘み (‘hatsutsumi’), written on the pack of the yaki nori (above photo, which happens to be from Ariake sea as well). It means the first flush of nori. A hatsutsumi nori sheet is tasty and very crunchy, but melts in your mouth as it disintegrates easily in liquid.
When I made Nori Sui with hatsutsumi nori sheet, I had to use a spoon to pick up the nori in the broth. I prefer Nori Sui with nori pieces still intact, but if you like the soft texture of melted nori in the soup, hatsutsumi might be the one you want to use for Nori Sui.
How to Make Roasted Seaweed Soup (Nori Sui)
Nori Sui is an extremely simple soup to make. Like a Sashimi dish, you need to do very little with it to make a delicious dish when you have a quality ingredient.
- Bring the broth to a boil.
- Roast the nori sheets over an electric cooktop, or a frying pan over high heat on a gas cooktop.
- Tear the sheets into small bite-size pieces.
- Put nori pieces and harishōga in a serving bowl.
- Pour the broth over.
To enhance the flavour of seaweed, you need to roast the nori sheets to make them very dry and crunchy. It also lets you tear them easily. This is particularly important if you are not opening the nori pack for the first time.
The traditional way of drying nori sheets is to toast them over a fire by holding two sheets together and quickly passing the nori over the fire several times on both sides. Gas cooktops produce moisture when they are burning, so you should use a heated frying pan and roast nori sheets on the pan (see the photo above).
Be careful not to heat the nori sheets too much. They will burn and start shrinking.
This technique can also be used when your roasted seaweed sheets become stale, which can easily happen after storing them in your pantry for a while.
Roasted Seaweed Soup is a simple soup but very elegant and full of nori flavour. You can use up to 2 full-size yaki nori per serving if you like.
By using different toppings, you can enjoy flavour variations.
Roasted Seaweed Soup (Nori Sui) is a clear soup with torn roasted seaweed and very finely julienned ginger (hairshōga). This is perhaps the simplest clear soup of all, but it is a luxury that uses an abundance of high-quality roasted seaweed sheets and the elegant flavour of the broth comes from a good dashi stock.
If you are a vegetarian, use konbu dashi.
Don't forget to see the section 'MEAL IDEAS' below the recipe card! It gives you a list of dishes that I have already posted and this recipe that can make up a complete meal. I hope it is of help to you.
Put all the Broth ingredients in a pot and bring it to a boil.
Take one yaki nori sheet at a time, put it through in a quick motion directly over the heat of an electric cooktop, or over a heated large frying pan on a gas cooktop that is set to high (note 3). Do this several times on both sides until the sheet becomes crisp.
Fold the nori sheets into quarters (so that you can handle them easily) and tear the sheets into small bite-size pieces - about 2.5cm/1” (note 4).
Put the nori pieces in a serving bowl and place harishōga on it.
Pour the hot broth over the nori pieces and serve immediately.
1. The standard size of yaki nori is 21cm x 19cm/8¼” x 7½, which is consistent across Japan.
Using quality yaki nori is very important for today’s dish. Please see the section ABOUT GOOD ROASTED SEAWEED SHEETS (YAKI NORI) in this post for what a good yaki nori looks like.
As a rule of thumb, the better the quality of yaki nori is, the more expensive it gets.
2. It is best to make your own dashi stock with konbu and bonito flakes (awase dashi) and use ichiban dashi. Please visit the section AWASE-DASHI, ICHIBAN-DASHI in my post, Varieties of Dashi Stock where the method of making a good dashi stock is explained, including konbu dashi for vegetarian.
3. When gas burns, it produces moisture which is counteractive to what you want to achieve. That's why you need to dry the nori sheets on a heated frying pan if your cooktop is gas, like mine. See the step-by-step photo that shows how I dried the nori sheet.
4. If the nori sheets are extremely crisp, you may even be able to scrunch them in a bag to make small pieces.
5. Nutrition per serviong.
serving: 217g calories: 45kcal fat: 1.7g (3%) saturated fat: 0.4g (2%) trans fat: 0.0g polyunsaturated fat: 0.3g monounsaturated fat: 0.5g cholesterol: 2mg (1%) sodium: 756mg (32%) potassium: 350mg (10%) carbohydrates: 2.1g (1%) dietary fibre: 0.2g (1%) sugar: 0.2g protein: 5.1g vitamin a: 8% vitamin c: 5.9% calcium: 1% iron: 1.2%