Portobello Mushroom Sandwich with Ranch Slaw

Meaty, juicy, savory, and crunchy, this portobello mushroom sandwich can be enjoyed by vegetarians and meat-eaters alike. Hearty portobello mushrooms are sauteed and topped with smashed avocado and a zippy and zesty ranch slaw. Satisfy your burger cravings in just 30 minutes with this healthy and delicious alternative.

Mushrooms are one of my all-time favorite foods. I love their meaty texture and deep umami flavor, but they're also excellent at absorbing flavor, so you can use them in a variety of cuisines, like in my vegetarian fajitas or vegetarian sloppy joes.

In this portobello mushroom sandwich recipe, we create an epic veggie sandwich full of flavors and textures that any meat-eater would enjoy. For more vegetarian sandwiches, try my garlic bread grilled cheese or french onion grilled cheese.

Jump to:

• ⭐️ Why This Sandwich is the Best
• 🍄 Preparing Portobello Mushrooms
• 🥪 Ingredient Notes
• 📝 Variations & Substitutions
• 🔪 How to Make a Portobello Mushroom Sandwich
• 👩🏼‍🍳 Expert Tips
• 💬 Frequently Asked Questions
• 🍽 Related Posts
• Portobello Mushroom Sandwich Recipe

⭐️ Why This Sandwich is the Best

• Meaty and juicy vegetarian sandwich topped with a crunchy and zingy ranch coleslaw
• Healthy mushroom burger that's full of antioxidants, B vitamins, fiber, potassium, and selenium (read more about the excellent reasons to eat mushrooms). It can easily be made vegan or gluten-free (see substitutions below).
• Quick & easy meal that's ready in 30 minutes
• Customizable sandwich that be finished with your favorite sandwich toppings
• Versatile mushroom burger that can be baked in the oven or cooked on the grill (see variations below)
• Perfect for summer cookouts or bbq's

🍄 Preparing Portobello Mushrooms

When using portobello mushrooms, make sure that you wipe them clean with a paper towel to remove any dirt. DO NOT WASH THEM WITH WATER. Mushrooms contain a lot of water, so adding more water will turn them soft and mushy.

The stems are edible but they do have a woody and fibrous texture, so some folks prefer to remove them. This is totally optional for this recipe. Similarly, the gills are also edible, but some people remove them because of the texture when cooked.

🥪 Ingredient Notes

• Portobello mushrooms - Large, meaty variety of mushrooms that are dark brown in color. They are considered the "mature" version of cremini mushrooms with a deeper flavor and have numerous health benefits.
• Mayonnaise - this is the base for our tangy slaw; it adds a creamy tanginess
• Buttermilk - adds even more tangy flavor
• White wine vinegar - adds zippy flavor; apple cider vinegar will work as well
• Garlic - I recommend using fresh garlic for the best flavor
• Ranch slaw seasoning: The seasoning for our ranch coleslaw is a mixture of dried dill, dried parsley, dried chives, onion powder and garlic powder.
• Shredded carrots and cabbage - Adds fresh flavor, crunch, nutrition, and a pop of color
• Hamburger buns - Use a sturdy type of bun or roll to help soak up all of the juiciness of the sandwich. Brioche buns, pretzel rolls, or ciabatta rolls all work great.

📝 Variations & Substitutions

• Make it vegan: Substitute with a vegan mayonnaise and omit the buttermilk completely, or skip the coleslaw altogether and top your burger with guacamole, pickles, or ketchup instead.
• Gluten-free: Use gluten-free hamburger buns or turn your sandwich into a wrap using lettuce leaves.
• Bake mushrooms: Instead of cooking on the stove top, bake your mushrooms in the oven for more of a roasted flavor. Preheat oven to 350 degrees F. Brush mushrooms with olive oil and place gill side up into a baking dish. Bake for 15 minutes, until tender.
• Grill mushrooms: Brush mushrooms with olive oil and place on the grill for around 10 minutes, flipping frequently.
• Cook your mushrooms using an air fryer. Preheat fryer to 375 degrees F. Lightly brush mushrooms with olive oil and place gill side up in fryer. Cook for 7-10 minutes, until tender.
• Make it a double. For a heartier sandwich, use 2 mushrooms per sandwich.

🔪 How to Make a Portobello Mushroom Sandwich

Make the mushrooms:

Wipe the mushrooms clean and remove the tough stems. Preheat a large skillet to medium heat, and add olive oil to skillet.

Working in two batches, sprinkle 2 mushrooms with a pinch of salt and place into skillet with gills facing up. Cook 4-5 minutes, then flip over and cook for an additional 5 minutes, until the mushrooms are firm-tender. Repeat with the remaining 2 mushrooms.

Make the ranch slaw:

Meanwhile, in a medium bowl, whisk together mayonnaise, buttermilk, vinegar, dill, parsley, chives, onion powder, garlic powder, and salt. Add shredded carrots and cabbage and stir until both are completely covered in sauce.

Assemble sandwiches:

To assemble sandwiches, smash ¼ of avocado (if using) on top half of a hamburger bun. Place cooked mushroom on bottom half of bun and add a generous scoop of the slaw on top. Serve immediately.

👩🏼‍🍳 Expert Tips

• Storage: Place mushrooms in an airtight container and store in the refrigerator for up to 4 days.
• Serve sandwiches with corn on the cob, mashed potatoes, vegetarian baked beans, or sweet potato fries.
• Removing mushroom stem is optional. It does have a woody and fibrous texture, but it is edible.
• Wipe mushrooms clean. Be sure to use a dry towel or paper towel to clean your mushrooms. Do not wash with water, as this will turn the mushrooms soft and mushy.
• Serve with your favorite toppings and condiments. You can skip the slaw altogether and use mayo, mustard, lettuce, tomato, or basil aioli instead.

💬 Frequently Asked Questions

🍽 Related Posts

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