The secret to delicious and savory vegan yakitori is fermentation. In this recipe, I’ll teach you how to harness umami through fermentation so you can kick real yakitori’s ass.

For a vegan ramen pop-up I hosted in San Francisco (see here for the vegan ramen recipe), I wanted to give myself a challenge. Could I replicate an even more meat-centric Japanese dish than ramen for this pop-up, too? I gave it a shot, and it was a surprising success.

For inspiration, I looked to Noma’s celery root shawarma. I still have no idea what they did to transform celery root into such a delicious dish, but I figured koji probably had something to do with it.

Koji, if you’re not aware, is the molded rice used to make miso, soy sauce, and sake. Like nature’s MSG, koji is by far my favorite way to add umami to vegan dishes.
My theory was that I could combine celery root with koji and other savory ingredients and cook it just like authentic yakitori. To my surprise, it worked. Really, **really** well.

What follows is the recipe I served at my pop-up. I grew my own koji to create this recipe (which is a whole other rabbit hole that I recommend you get in to), but this recipe will call for store-bought koji. Still, since the recipe relies on a fermentation process, it will still take a week or longer. But it’s worth it! You’ll thank me later.

This serves ~6 people.

Ingredients

Shio koji marinade:
- Salt: 100g
- Rice koji: 400g
Hazelnut puree:
- Raw hazelnuts, 100g
- Neutral oil, 60g
- Water, 60g
- Lemon juice, 20g
- Salt to taste

3 celery roots, peeled
Sake
Apple cider vinegar

Step 1: MAKE THE Shio koji

Shio koji is a sauce made from lacto-fermented koji (which is the molded rice used to make miso and soy sauce). You can use shio koji to marinate meat or veggies and really take them to the next level. But here, I use it add umami, acidity, and mouthfeel to the celery root yakitori. Since the fermentation process converts starches into sugars, the shio koji will also create beautiful char marks on the yakitori when we cook it. You can make this weeks in advance.

I highly recommend fermenting this yourself. It’s very easy, though it takes 7 days. But if you must buy some instead, try this. It won’t be the same, but it’ll work in a pinch.

I’ll walk through the steps to make shio koji, but at a high level, you just combine 4 parts rice koji, 1 part salt, and 5 parts water. Then you let these ingredients sit at room temperature in an air-tight space for 7 days. Over those 7 days, the salt protects the other ingredients from bad bacteria, but good bacteria (which is resistant to the salt) breaks down the starches into their component parts. These component parts have more umami and acidity than the ingredients themselves. The end result is a powerful, salty brew of beautiful umami.

If you’ve never fermented like this before, it’s surprisingly easy. And it’s actually how pickles, sauerkraut, and kimchi are made. You just need a few pieces of equipment to make sure it is safe. Here’s what I use.

1. Wide-mouth mason jar: This is where we will store the rice, salt, and water as it ferments into shio koji.

2. Fermentation lid: When the fermentation is doing its thing, air escapes. We want air to exit the mason jar so that it doesn’t explode from built-up pressure. But we also don’t want to let air in (because that can let the wrong bacteria take hold). This lid has a one-way valve to allow for this.

3. Kitchen scale: You need a scale that measures to the gram, because we’re going to add a very specific amount of salt that enables the good bacteria to do its thing while the bad bacteria can’t.

4. Rice koji: This is the molded rice used to make soy sauce, miso, mirin, and sake. A staple in Japanese cooking, think of it like natural MSG. It’s the secret behind this recipe’s ability to taste as savory as a dish with meat.

I personally grow my own koji on barley using the Noma Guide’s recipe, but this works just as well.

Once you have all the ingredients, here are the steps for making shio koji:

Combine 500g of water with 100g of salt. Mix in the mason jar until fully incorporated.
Add 400g of rice koji and mix well.
Tighten the fermentation lid and leave it in a dark place at room temperature.
The next day, confirm that the rice has not soaked up all the liquid. If it has and the rice is exposed to the air, add a bit more liquid until the rice is submerged. Don’t add too much because then you will mess up the salt to water/koji ratio.
After 7 days, taste to ensure that it has developed a sourness similar to sauerkraut. If it has, you are done fermenting! If it hasn’t, you can wait a couple more days.
Add to a blender to turn it into a fine puree. You can now store this in the fridge for months and use it to marinate things.

Step 2: MAKE THE Hazelnut puree

The hazelnut puree adds a nutty flavor to the yakitori. It also forms a bond of sorts between each piece of celery root, making the dish look more like yakitori after it’s cooked. You can make this a couple days in advance.
Combine all ingredients in a blender.
Blend on high for 5 minutes. You are blending this long at such a high speed to lightly “toast” the hazelnuts. We’re cooking with blenders up in here!
Salt to taste

Step 3: MAKE THE celery root

Next, we’re going to pre-cook the celery root so that it only needs to be seared later on. I recommend doing this a few hours before serving so that the celery root can marinate in the shio koji longer.

Peel and wash the celery root
On a pan, cook it in an oven at 300f for 1 hour. It should be soft enough to slice easily.
Once it has cooled, slice it on a mandoline at about 1/8th inch thickness.
Spread the shio koji on the sliced celery root and keep it in the fridge to marinate for at least an hour.

If you don’t have a mandoline yet, I highly recommend this one. Unlike the cheaper Japanese mandolines, this one has a very sturdy stand (and a hand guard), which makes using the mandoline feel safer. It also has specific measurements so you know exactly how thin you are slicing.

Step 4: Assemble THE yakitori

With this step, we’re prepping the yakitori for cooking.

Spread the hazelnut puree with a fine coating on each of the celery root slices.
Slide the celery root slices onto wooden skewers. Try not to leave a big space between the celery root and the point of the skewer, because you really don’t want your guest to have to deep-throat the skewer to eat the yakitori.
Store in the fridge until ready to serve.

Step 5: Cook that vegan yakitori!

It’s game time! But this part definitely takes the most practice.

Traditional yakitori is cooked over binchotan. This rare, dense charcoal is known for having a long burn time without much smoke. The good part about that is that electric grills actually do a pretty good job of simulating the experience, far more so than a traditional charcoal grill. So we’re going to use an electric grill to do this.

When grilling the yakitori, you want to use a high heat. Throughout the cooking process, there are a few steps you can take to improve the quality of the product.

Rotate the skewers occasionally. To roast the hazelnut puree a bit, you should aim for at least a few full rotations while cooking this, so feel free to rotate more than you would a traditional skewer.
Spray with sake! Have a spray bottle on hand with some sake. Spraying will help to caramelize the dish a bit while also preventing it from over-charring. Save this until the yakitori is nearly cooked through all the way.

Once you’ve cooked the yakitori completely and it has nice coloring, remove from the grill. Before serving, spray with a little bit of apple cidar vinegar (I actually always keep different vinegars in little spray bottles for last minute touch-ups). You can also add togarashi for some spice.

And that’s it! Hope you enjoy it as much as my guests at the pop-up did.

Vegan Yakitori Recipe