Vegan Dashi Broth (Easy Shiitake & Kombu Soup Stock)

Learn how to make flavorful vegan dashi with just kombu and dried shiitake. No cooking needed,  just soak and enjoy a rich, umami-packed broth!

Have you been skipping Japanese dashi because it usually includes bonito flakes, which aren’t vegan or vegetarian? Then this vegan dashi recipe is for you!

With just two plant-based, umami-rich ingredients, you can make a dashi broth that tastes just as good as classic awase dashi. Really.

I’ll also explain why this version tastes better than basic kombu dashi or shiitake dashi, and how the ingredient combo creates that deep, satisfying flavor.

💡Curious about dashi? Check out my complete Dashi Guide to learn all about it!

Why You'll Love This Recipe

• No cooking needed: Just soak the ingredients and let time do the work. That’s it! The umami builds while you go about your day.
• Plant-based, no flavor sacrifice: By combining two umami-rich ingredients, you’ll get a dashi that’s just as flavorful as the classic kombu and bonito version (I’ll explain the science behind it too!).
• Easy to customize: I’ll show you how to adjust the ingredient-to-water ratio so your dashi works perfectly for whatever you’re making, miso soup, mentsuyu, or anything in between.

Notes on Ingredients

See the recipe card for the full ingredients list.

Kombu (Dried Kelp)

In Japan, four main types of kombu are used for making dashi: Rishiri, Ma, Rausu, and Hidaka.

For vegan dashi, which combines kombu with dried shiitake, you want a kombu that has a noticeable flavor but isn’t too strong. Ma kombu and Rishiri kombu are the best choices, but they can be difficult to find and tend to be pricey outside Japan.

If you’re in the U.S., try to find kombu that:

• Comes as large sheets, not pre-cut strips
• Is thick and firm to the touch

I tested WEL-PAC Dashi Kombu, and it worked great.

👉 Quick tip: The white powder you see on kombu isn’t mold, it’s natural glutamate, which adds umami. Avoid rinsing your kombu because you’ll wash away that flavor.

👉 Why not just use MSG?

Kombu naturally contains umami plus minerals and nutrients, while MSG only imitates umami without the added health benefits.

Dried Shiitake

There are two main types: Koushin and Donko. They’re the same mushroom but differ in appearance.

• Koushin: Bigger, thinner caps that are more open. This means umami extracts more easily.
• Donko: Thicker, rounder caps.

Flavor-wise, they’re similar, but:

• Choose Koushin if you want the ease of making dashi and a better price.
• Choose Donko if you want a thicker, chewier texture or nicer presentation.

Water

Water quality plays a bigger role in dashi flavor than many realize. Soft water is preferred because it extracts more umami from the ingredients.

Hard water, which contains higher levels of calcium and magnesium, can make it harder to draw out flavors and might cause the broth to become cloudy or bitter.

Since most tap water in the U.S. is hard, I recommend using a water filter like Brita to soften it. This is a more affordable and environmentally friendly option compared to buying bottled soft water each time.

💡You can find these ingredients at Japanese or Asian grocery stores, or online at Amazon or Weee!

Substitutions and Variations

• Kombu: If you can’t find kombu or need to avoid it, try dashi options that don’t use it, like shiitake dashi. You can also experiment with kombu substitutes such as MSG powder or kelp-based dashi powder (kombu granules).
• Dried Shiitake: There aren’t many ingredients that are rich in guanylic acid, so dried shiitake is tough to replace. Other foods like fresh mushrooms, dried tomatoes, or nori seaweed do contain guanylic acid, but not nearly as much. If needed, you can use shiitake powder or just stick to a different type of dashi like kombu dashi.
• Shortcut Options: If you forgot to soak the ingredients or need dashi in a pinch, dashi powders are a great backup. To make a quick vegan version, mix kombu dashi powder and shiitake dashi powder, or use a vegan-friendly dashi pack.

💡Think About What You’re Cooking: The key to a flavorful dish is combining an amino acid (like glutamate) with a nucleic acid (like guanylate or inosinic acid). So if you’re swapping ingredients, try to add back the missing umami component somewhere else in the dish.

For example:

• If you can’t use kombu, make shiitake dashi (rich in guanylate) and cook with tomatoes or onions (which are high in glutamate).
• If you can’t use dried shiitake, make kombu dashi (rich in glutamate) and use mushrooms or dried tomatoes (which contain nucleic acids).

👉 If you're curious, here's a list of umami-rich ingredients by their umami compound.

Why Mix Both Kombu and Shiitake?

There are three main types of umami compounds:

• Glutamic acid (an amino acid)
• Inosinic acid and guanylic acid (nucleic acids)

Research shows that combining an amino acid with a nucleic acid makes the umami flavor much stronger, and this is called umami synergy.

Kombu is packed with glutamic acid, while dried shiitake is rich in guanylic acid. That’s why vegan dashi, which uses both, tastes richer and more savory than dashi made from just one ingredient.

Total Ingredient-to-Water Ratio (by weight)

You can adjust the amount of kombu and dried shiitake depending on how you plan to use the dashi.

For example, if you're using 1 liter of water, a 3% ratio means using a total of 30 grams of kombu and dried shiitake combined.

How to Make Vegan Dashi

Step 1: Lightly wipe the surface of the kombu and dried shiitake.

Step 2: Soak all the ingredients in the fridge for 10 to 12 hours and remove the dashi ingredients.

Reusing Dashi Ingredients

Don’t throw away your used kombu or dried shiitake! You can still turn them into tasty, no-waste side dishes and seasonings. Here are a few easy ideas:

• Furikake: Chop the ingredients into small pieces, dry-sauté in a pan, and season with soy sauce and mirin. Sprinkle over rice or veggies for an umami boost.
• Tsukudani: Slice into thin strips and simmer with soy sauce, mirin, and sake until soft and flavorful. It stores well and goes perfectly with rice.
• Onigiri Filling: Use tsukudani as a savory filling or mix-in for rice balls.
• Dashi Ponzu: Soak chopped kombu or shiitake in ponzu sauce. The added umami is great with grilled dishes like salmon.
• Dashi Soy Sauce (Dashi Shoyu): Soak the used ingredients in soy sauce to create a versatile, umami-rich seasoning for stir-fries, tofu, or fried rice.
• As an Ingredient: Use the rehydrated shiitake mushrooms in simmered dishes

How to Use Vegan Dashi

You can use vegan dashi in just about any dish, especially those that already include other umami-rich ingredients, like miso soup or simmered dishes.

But don’t stop at Japanese food! Vegan dashi works great in non-Japanese recipes too. For example, you can use it as a base for soups or to add a rich, savory flavor instead of butter or milk.

Storage Instructions

• Dashi: Store in an airtight container for up to 3 days in the fridge or 2 weeks in the freezer (ice cubes work great for small portions).
• Used dashi ingredients (kombu and rehydrated shiitake): Pat dry and store in an airtight container for up to 1 week in the fridge or 1 month in the freezer.

FAQs

Explore Other Types of Dashi

Vegan dashi is just one of several delicious types of dashi, and each one has its own unique flavor and use.

If you’re wondering what makes each type different or how to choose the right one for your cooking, check out my Ultimate Guide to Dashi. It covers everything from the basics to ingredient tips, and it’ll help you find the best dashi for your kitchen.

Ready to try more? Here are other dashi recipes you might like:

• 🍄 Shiitake Dashi
• 🐟 Kombu Dashi
• 🌱 Vegan Dashi (You’re here!)

🎁Grab your FREE dashi cheat sheet! Stick it on your fridge and skip Googling recipes every time 🙂

🎁FREE Dashi Cheat Sheet