Roasty portobello strips, golden caramelized onions, melted Provolone cheese, zippy horseradish aioli, all piled on a warm, crusty roll.
Portobello French Dip with Horseradish Aioli
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This was so amazing! My 6 year old and 4 year old kept asking for bites so I had to make them their own, and my 4 year old finished and told me he would eat these everyday! Got them to eat veggies without begging them to finish!
Karen
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It’s hard to describe how much there is to love about these sandwiches, but I’ll try:
Crunchy, buttery, toasted bread is going to meet up with roasted steak-seasoned portobello strips, sweet and golden caramelized onions, a sheet of melted Provolone, and a big thick smear of horseradish aioli…
And then just when you think it can’t even get any better, that whole beautiful crispy, saucy, golden sandwich gets dunked in a richly savory, no-meat-necessary, au jus dipping sauce.
It is wonderful, it is meatless, it is the epitome of comfort food.
Watch How To Make This Recipe:
French dips are a type of sandwich that normally contain beef, onions, and cheese (also called beef dips) and their trademark is that they get dipped in an au jus (brothy kind of sauce). According to this nice little history of French dips, they are an American invention, but they’re called French due to the type of bread usually used.
Common Questions About French Dips
What can I substitute for Worcestershire sauce?
You can use vegan Worcestershire sauce or substitute soy sauce.
What can I use instead of white wine?
You could add a little bit of water instead.
How can I make this gluten-free?
We’d suggest using gluten-free Worcestershire sauce, tamari or coconut aminos in place of soy sauce, and using a gluten-free baguette or roll.
Portobello French Dip with Horseradish Aioli
- Total Time: 45 minutes
- Yield: 4 mega sandwiches 1x
Description
These Portobello French Dips are about to change your life! Roasty portobello strips, golden caramelized onions, melted Provolone cheese, zippy horseradish aioli, all piled on a warm, crusty roll.
Ingredients
Scale
Roasted Mushrooms
- 4 portobello mushroom caps, sliced into thin strips
- 2–3 tablespoons olive oil
- 1–2 teaspoons Montreal steak seasoning (or just a sprinkle of salt and pepper)
Caramelized Onions and Au Jus
- 2 tablespoons butter
- 1 large onion, thinly sliced
- 1/4 cup white wine
- 1 tablespoon Worcestershire (omit for vegetarian / vegan)
- 1 tablespoon soy sauce
- 2 cups beef or vegetable broth
- salt, pepper, and a pinch of sugar to taste
Horseradish Aioli
- 1/2 cup mayo
- 1 teaspoon horseradish
- 1 clove garlic, grated
- pinch of salt
French Dip Essentials
- 4 crusty sourdough rolls, or a baguette cut into 4 sections
- Provolone cheese slices
Instructions
- Roast the Mushrooms: Preheat oven to 450 degrees. Toss mushroom slices with oil and seasoning. Roast for 20-30 minutes.
- Caramelize the Onions: Meanwhile, melt the butter in a large skillet over medium heat. Add onions; saute until softened, then turn the heat down to caramelize the onions for 20 minutes or so, stirring occasionally until they are deep golden brown.
- Make the Au Jus: Add the wine to the onions in the pan. Let it sizzle out. Add the Worcestershire and soy sauce. Add the broth. Simmer until reduced slightly. Pull out the onions with tongs and set aside. Season the au jus to taste.
- Toast the French Dips: Butter the bread if you want. Pile mushrooms on the bread. Cover with cheese. Return to the oven on the same roasting pan for about 5 minutes (enough to toast the bread and melt the cheese).
- Feast: Top the sandwiches with caramelized onions. Give em each a dollop of horseradish aioli. Serve with the au jus for dipping! HOLY MOLY that’s good.
Equipment
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- Prep Time: 15 minutes
- Cook Time: 30 minutes
- Category: Sandwich
- Method: Oven
- Cuisine: American
Keywords: portobello mushrooms, french dip, vegetarian sandwich, caramelized onions
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One More Thing!
This recipe is part of our collection of delicious mushroom recipes. Check it out!
Filed Under: All Recipes Dinner Main Dishes Mushroom Plant-Powered January Recipes Sandwiches Vegetarian Winter
January 11, 2021
Nice to meet you!
I’m Lindsay and I ♡ FOOD. I used to be a teacher, and now making food and writing about it online is my full-time job. I love talking with people about food, and I'm so glad you're here.
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Oh my gosh, I have been talking for the last few weeks about being uninspired with my cooking. This is EXACTLY what I needed to get super excited about a meal and out of my rut! I cannot wait to make these – YUM!!
Enjoy, Kylie!
OK, it’s barely past breakfast time, and I am drooling for one of these!!!
Adding a stop at the local grocery to my list today, to snag those mushrooms and some bread… THANK YOU!
Hope you enjoy them, Cricket!
That looks absolutely great and delicious.
What do you line your baking sheet with in the video. ( It isn’t just parchment paper.)
Thanks
Hi Dale! It doesn’t look like we’ve used any lining on the baking sheets. It could be the texture/pattern of the baking sheet that you’re seeing.
I just made these and they are excellent. They were easy and so fulfilling to eat. Thank you…..
So glad you liked them, Karen!
Is the white wine a must…?
It definitely adds a nice rich flavor, but you could just use more broth instead!
Or are there any substitutions?
Another amazing recipe. This is really soooooo good. I used apple cider vinegar since I didn’t have any white wine laying around. It was great!! Thank you for all of your recipes.
This was so amazing! My 6 year old and 4 year old kept asking for bites so I had to make them their own, and my 4 year old finished and told me he would eat these everyday! Got them to eat veggies without begging them to finish!
Such a win, Karen! 🎉 Thanks so much for the comment!
Made this as soon as I saw it! It was SO good. It was impossible to eat, in the best possible way. Easy and quick enough to make on a weeknight. My only frustration was after roasting the mushrooms, I had no where near enough for 2, let alone 4 sandwiches. I used four pretty decent sized portobello mushrooms. But they shrunk SO much. I ended roasting a bunch of white mushrooms to be able make up enough for two sandwiches. But otherwise it was a great meal!
Great feedback, Hilary. Thanks so much for reporting back!
I thought these were soooo delicious but I had a similar issue where I actually roasted 6 portobello caps and only had enough for 2 sandwiches because they shrunk up so much in the oven. I was so disappointed because I was reaaally looking forward to a leftover sandwich!! 🙂 it was yummy!!
Glad you enjoyed the recipe! And thanks so much for the feedback, Megan!
This was SO good! I also agree with other commenters that the mushrooms not being enough for four sandwiches. Two sandwiches was very filling for two people but would have loved to have had leftovers.
Made these last night, so satisfying, even my carnivorous husband loved them! Next time I will slice the portobellos a bit thicker so they don’t shrink down as much and broil the bread before the step of melting the cheese over the mushrooms. Made a second batch with shiitake mushrooms and it was also delicious. Thank you!!
Oooh shiitakes sound wonderful! So glad you and your husband enjoyed the sandwiches!
This recipe was amazing! I made it for lunch today and I will definitely be making this a part of my weekly routine.
So happy to hear that, Lanie!
Made this tonight and it was soooooo good!!
Thank you for this, a great alternative to beef.
So glad you enjoyed it, Jennifer!
Made a special stop at the grocery store to get the ingredients and made this tonight. So freaking delicious!
Glad to hear it, Carolyn!
Made these last night and they were AMAZING! My husband, who has to have meat with every meal, inhaled them and said we need to have them again soon! I agree, I didn’t have enough mushrooms but I will totally make again and again! Everything I’ve made from your site have been delicious! Great Recipe! Thank you!
We love hearing this, Jessica!
you can try a light salting of the mushrooms, it will draw the moister out and they will reduce more.
This is honestly one of the best sandwiches I’ve ever had in my life. All of the flavor you could dream of but none of the heavy meat feelings.
We are thrilled to hear that, Cristal!
I never saw this on the menu at the local Italian restaurant when I was growing up in Brooklyn. We had meatball Parmesan sandwiches, baked ziti, baked lasagna, spaghetti and meatballs, eggplant Parmesan subs, and garlic knots. But I don’t recall seeing portobello mushroom Parmesan sandwiches. This certainly looks good and gives someone a like to think about in making a homemade portobello mushroom Parmesan sandwich with tomato sauce. Certainly looks delicious to me! 🙂
We love where you’re going with the mushroom parm sandwich idea! If you give this one a try, we hope you love it!
I made this for dinner tonight. Just delicious….I heard audible yum sounds from my husband as he ate.
We love hearing this, Marlene!
Made this for lunch today! That jus was jus-t perfect. OMG I can’t want to make it again. The mushrooms are incredibly delicious!!!
Thanks for giving the recipe a try! We’re so happy you enjoyed it!
This is now my most favorite recipe on Pinch of Yum (which is a huge statement given the fact I was basically the Falafel-Veggie-Naanwich Ambassador and practically handed that recipe out as flyers to anyone and everyone). SO flavorful and easy! 5-stars is an understatement!
I made this tonight, and it was delicious! I cut the portobello into wider strips and used more mushrooms, as per the other comments. The horseradish aioli was a nice addition too!
OMG! It was amazing!!! Great recipe.
Glad you liked it, Alicia!
Can’t wait to try this. Thank you for sharing!
Enjoy!
OH MY GOSH. I’m an omnivore and this was hands down the best French dip sandwich I’ve ever had! Made it for dinner tonight and it was absolutely SCRUMPTIOUS! Perfectly savory, creamy, just straight-up delicious! Thanks for a great recipe!
Awesome Alex! We’re so glad you enjoyed it!
cant wait to try this this week
We hope you love the recipe!