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This Asian-style, grilled, vegan Portobello Mushroom Burger is full of delicious umami flavor! It’s slathered with Asian-style Guacamole, and topped with a cool cucumber ribbon salad and crunchy carrot slaw. Healthy, delicious, vegan. Video!
Oh my goodness, this Portobello Mushroom Burger is so delicious! A flavorful umami bomb! Portobello mushrooms are brushed with a Miso-Sesame-Sriracha marinade, then grilled or roasted until perfectly juicy and tender.
They are layered up with a Japanese-style cucumber ribbon salad, a carrot slaw (or Asian Slaw) and the best part, as Asian style, avocado spread for the buns- seasoned with ginger & sesame, (aka Asian Guacamole). Full of flavor… and totally vegan!
Portobello Mushroom Burger | 60-Second Video
Portobello Mushroom Burger Ingredients
- Marinated Portobello Mushrooms- can either be grilled or roasted
- Mashed Avocado “the sauce” – hold the burger to geher
- Cucumber Ribbons
- Crunchy Asian Carrot Slaw (or sub-Asian Slaw)
- Buns (or try Sourdough Buns!)
A few components, but honestly doesn’t take too long to put this together.
How to make Portobello mushroom Burgers
Step 1: Prep the portobello mushrooms ! Make the flavorful marinade. The umami flavored miso paste, blended with sriracha and sesame oil is delicious on portobello mushrooms!
Step 2: Make the cucumber ribbon salad!
Cut baby cumbers into thin ribbons using a mandolin or veggie peeler. Or just cut them into thin disks, no problem! Season with the dressing!
Step 3: Make the quick carrot slaw. I just used store-bought match stick carrots for this , but feel free to grate a carrot! You can also sub this Asian Slaw!
Step 4: Make the Mashed Avocado Spread…. or “Asian Guacamole”.
Mash up a large avocado with fresh ginger, sesame oil and a splash of rice vinegar.
Step 5: Roast or Grill the portobello mushrooms for the burgers. I always start with tops down…they’ll dry out less. Grill for 4-5 minutes over medium heat, giving them a nice sear, flip and cook for a couple more minutes. If you are particular like me, collect the juice from the mushroom caps before flipping and use that to baste the tops. Optional, but keeps them moist. 😉
Step 6: Toast the buns! This is essential…..it keeps them from getting soggy!
Step 7: Assemble the Portobello Burgers!
Spread the toasted buns lavishly with Avocado spread. This will keep the buns from getting soggy. Top with the grilled portobello mushroom, gill- side up -to collect all the flavorful juices in the burger.
Pile everything on top of the grilled portobello.
Spread the bun tops with more avocado spread, and top the burger. Or, for a lower-carb option, feel free to serve the portobello burgers, open-faced, with knife and fork.
Other additions…..a squirt of sriracha and a little pickled ginger is nice.
This is my favorite portobello mushroom burger and I can’t wait for you to try this and tell me what you think!
xoxo
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Portobello Mushroom Burger
- Prep Time: 25
- Cook Time: 10
- Total Time: 35 minutes
- Yield: 2 1x
- Category: Vegan, main, sandwich
- Method: grill
- Cuisine: Japanese, Asian, american
Description
This Asian-style, portobello mushroom burger is full of delicious umami flavor! It’s lathered with Asian-style Guacamole, topped with a cool cucumber ribbon salad and crunchy carrot slaw. Healthy, delicious and really satisfying. AND totally vegan!
Ingredients
- 2 large portobello mushrooms
- 1 Tablespoon Miso ( any color)
- 1 tablespoon toasted sesame oil
- 1 tablespoon sriracha
- pinch of salt and pepper
Cucumber Ribbon Salad
- 2 turkish cucumbers, cut length-wise into ribbons ( use a mandolin– see notes)
- 1 scallion, sliced at diagonal
- 1/4 teaspoon salt
- 1/4 teaspoon sugar
- 2 teaspoons rice vinegar
- 1/2 teaspoon toasted sesame seeds
Carrot Slaw ( to simplify this, see notes)
- 1 1/2 cups matchstick carrots ( or grated)
- 1 scallion
- 1/4 teaspoon salt
- 1/4 teaspoon sugar
- 2 teaspoons rice vinegar
- 1/2 teaspoon toasted sesame seeds
Asian Guacamole
- 1 extra large avocado, cubed
- 1 teaspoon finely chopped ginger ( or use ginger paste)
- 1 teaspoon rice wine vinegar
- 1 teaspoon sesame oil
- 1/4 teaspoon salt and pepper
- pinch chili flakes and sesame seeds
2 whole wheat buns, grilled
Optional additions- pickled ginger
Instructions
Preheat the grill or oven. ( See notes for roasting in oven) Using a fork or mini whisk, mix the miso, sriracha, and sesame oil ….& pinch salt and pepper together in a small bowl to make a paste. Brush liberally onto both sides of the portobello mushrooms.
Using veggie peeler or mandolin, cut the cucumber into long thin ribbons. (You can always just slice them into very thin disks) Place them in a medium bowl along with scallions and add the dressing ingredients and gently toss.
Make the carrot slaw the same way. Place in a small bowl, toss with dressing ingredients. To save time you can combine both the carrots and cucumber (and double the dressing) and serve them together in one bowl – but I prefer them separate, just for “prettiness”, but it’s not essential. 🙂
Make the Asian Guacamole, by placing everything in a small bowl, mashing and stirring a bit until creamy and combined. It doesn’t have to be smooth. Sprinkle with sesame and chili flakes.
Grill the portobellos, top sides down first, for 4-5 minutes over medium heat, until juicy and tender. Flip, grill a few more minutes. Grill the Buns.
Assemble the burgers….spread buns with generous amount of Asian Guac, place the portobello- gills side up ( to catch all the flavorful juices) then mound with cucumber ribbon and carrot salad, a little squeeze of sriracha, optional pickled ginger. Use the remaining Asian Guac on the bun tops, and top the burgers.
Eat immediately.
Notes
Portobellos can also be roasted in a 400 F oven- gills up, for 15 minutes, flip, and roast 5 minutes more.
For a lighter meal you could serve these open-faced, with knife and fork without the top bun.
To save time you can combine the both the carrots and cucumber (and double the dressing) and serve them together in one bowl – but I prefer them separate, just for “prettiness”, but it’s not essential. 🙂
Nutrition
- Serving Size:
- Calories: 415
- Sugar: 12.7 g
- Sodium: 701.6 mg
- Fat: 21.2 g
- Saturated Fat: 3.2 g
- Carbohydrates: 48.1 g
- Fiber: 12.9 g
- Protein: 6 g
- Cholesterol: 0.5 mg
Keywords: vegan burger, portobello burger, vegan portobello burger, grilled portobello burger
Excellent recipe! I was surprised how filling these were. And the Asian guacamole was a great idea! Will definitely make again.
★★★★★
Awesome to hear Mary!
These burgers are the best!
So glad you are enjoying Jennifer!
Wow! What a delight. Because of the weather, we cooked the portobellos on the stove, and they were great. We had to eat with fork and knife. Loved!
Glad you were able to make it work!
What a surprise! Incredible taste and texture! Delicious!!!!
★★★★★
Happy you liked them Karen!
I thought the bun was a bit dry. I would do open face next time.
★★★
Shoot- sorry to hear that Nicole. It’s a pretty juicy one in general, I wonder if it could have been the bun itself?
Fantastic! Another winner from Sylvia! Love the color, texture and the flavor is a surprise! We love it! Thanks Sylvia!
thanks so much Karen!
Can’t find miso paste can I leave it out or replace with something else
Hi Pina- How about using soy sauce- maybe just 3/4 tablespoon.
This recipe was absolutely delicious! Super simple, very few ingredients, under 15 minutes. Amazing! Thank you so much.
★★★★★
Great to hear!
Wonderful flavor and textures, a winner at our house.
★★★★★
Sherry, thanks so much!
Delicious combination of flavors and textures.
★★★★★
Thanks so much and happy you enjoyed!
One of my favorite recipes on this blog and easily the best mushroom burger that I’ve had. The miso marinade is incredible! My husband and I look forward to making this every summer. I recommend doubling it and saving the left overs for bowls over rice.
★★★★★
Fantastic Susie! The rice bowl is a great idea.
Hi! what do you mean by “anal” in step 5?
★★★★★
Typo 🙂
Soooo good! My husband and I love Portobello burgers and have never had one this good. The umami flavor of the mushroom pairs so well with the fresh veggies (especially when they’re straight from the garden). Right after the first bite we knew this recipe would be a “keeper”. Highly recommended!
★★★★★
Great to hear Monica- thank you!
Now I want Asian guacamole every day. Thank you. Your recipes never disappoint!
★★★★★
Haha! Love it Allison! 😉
Ooh, this was so good- great range of flavors and textures unlike anything I’ve ever tasted. I used a slaw mix instead of carrots, but followed the recipe as is. A keeper for sure, and enjoyed by all, even the meat eaters.
★★★★★
Awesome!
I’m a vegetarian but my family is not. I served this entire meal as our 4 th of July Barbecue- it was fabulous and no one missed the meat. I served it with the Asian slaw. For starters I made veggie spring rolls with peanut sauce to set the mood and of course drinks. Thanks for a wonderful meal!!!
★★★★★
thanks Debra!
Bought soybean paste instead of miso by mistake…will that work? If so how much should I use…it seems extremely salty.
Ahhhh! Shoot Mari! I’ve never tried it. Miso is salty too though. Maybe start with half, add more to taste?
So delicious and so much flavor! I made these three days in a row. I can’t wait to try more of Sylvias recipes.
★★★★★
Thanks Jill!
I’m looking forward to making this! What would I serve as a side dish?
How about something light like Asian Slaw, or baked sweet potato fries?
You really don’t need a side with this recipe. However, I served it with speared cucumbers and extra guacamole for dipping. A red or yellow bell pepper and cherry tomatoes would be good for dipping also.
★★★★★