This post may contain affiliate links. Please read my disclosure policy.
If you cook for more than yourself, I’m sure you’ve had suggestions or requests for special dishes from time to time. My husband recently asked me to make French Onion Soup sometime. I started thinking about a recipe and immediately got stuck at “beef broth.” Not my favorite broth flavor for sure but I adore caramelized onions, french bread and cheese – so how could I make the soup without beef broth? I started thinking about an open face sandwich layered with onions and cheese, then moved on to a panini and finally got stuck on a the idea of a French Dip with Mushroom Jus. We have almost all the ingredients that come in a good French Onion Soup – cheese, bread and onions with a special bonus of mushrooms and mushroom jus (for dipping.)
I don’t think this completely cured his French Onion Soup craving, but boy it sure came close! The mushroom jus (a/k/a mushroom stock or broth) is wonderful for dipping and it’s also vegetarian so if you’re looking for an occasional meatless meal, this one is “that something special and different” and did I mention … it’s also absolutely delicious!
Portobello Mushrooms are baked until tender, sliced and heaped on top of garlic toasted french baguettes. The mushrooms are then topped with caramelized onions and provolone cheese. The sandwich is placed under the broiler for just a minute or two or until the cheese is melted and gooey.
The mushroom jus is made by simmering garlic and mushrooms until reduced into a nice thick broth. Soy Sauce, Liquid Aminos or Tamari is then stirred into the strained broth and served with the sandwiches. The mushrooms are juicy, the onions are sweet and soft, and the cheese is dreamy creamy. What a treat!
- 8 ounces baby Portobello mushrooms, and the stems from the sandwich mushrooms - below
- 4 large cloves of garlic, lightly crushed
- 1 1/2 tablespoons soy sauce
- 6 cups water
- 2 tablespoons unsalted butter, softened
- 1 teaspoon fresh thyme leaves
- 1/2 teaspoon minced garlic
- salt and fresh ground pepper
- 16 ounces baby Portobello mushrooms, stems removed and reserved for the mushroom jus
- 3 tablespoons olive oil, divided
- 1 teaspoon minced garlic
- 1 teaspoon crushed red pepper flakes
- 2 medium yellow onions, sliced thin
- 8 slices Provolone cheese
- 1 baguette
- To prepare the mushroom jus, gently wash the mushrooms with a wet paper towel to remove any dirt or debris. Place the mushrooms and 4 large garlic cloves in a medium saucepan. Cover with 6 cups of water and bring to a boil over medium-high heat. Lower the temperature to medium or medium/low, enough to maintain a low boil, and cook, uncovered for about 2 hours or until the jus is reduced to about 1 1/2 cups and slightly thickened. Strain the broth removing the mushrooms and garlic and discard. Stir in the soy sauce or tamari. Keep the jus warm if using immediately or refrigerate until read to use.
- In a small bowl combine the softened butter, thyme, 1/2 teaspoon minced garlic and a little salt and pepper. Set aside.
- Preheat oven to 350 degrees.
- Place the 16 ounces of cleaned mushrooms (stems removed and used in the jus) in a large bowl. Drizzle 2 tablespoons of olive oil over the mushrooms and toss with 1 teaspoon minced garlic and 1 teaspoon crushed red pepper. Place the mushrooms, gill side down, on a baking sheet and cook in the preheated oven for 25 minutes.
- While the mushrooms are in the oven, start the onions. In a large non-stick skillet, drizzle the remaining 1 tablespoon olive oil and heat on medium/high until shimmering. Add the sliced onions and cook until they start to soften. Reduce the heat to medium/low and continue cooking the onions, stirring occasionally, until they are caramelized. Set aside.
- Preheat oven broiler to LOW
- Remove the rounded ends from the baguette. Cut into 4 pieces and slice each piece in half. Spread each slice with the butter and thyme mixture. Place in the oven and broil until lightly browned and the butter is melted.
- Remove from the oven and divide the mushrooms on the 4 bottom halves of the baguette. Top each with 1/4 of the onions and then two slices of provolone cheese. Broil for a few minutes, just until the cheese is melted.
- Season with pepper and serve with warmed mushroom jus.
- If you have leftover mushrooms, refrigerate and use in an omelette or a small pizza. If your baguette is wider than mine you may be able to fit all the mushrooms on the bread.
- Recipe inspired by Vegetarian Portobello French Dip Sandwich by Cafe Flora Cookbook
I hope you had a lovely weekend. It was beautiful, but cool, here in Virginia. We’ve been so crazy busy lately that I was thrilled to finally get back in the kitchen. I hosted a baby shower last weekend for our son and daughter-in-law. They’re expecting their first baby (a girl!) in early April. They have so many friends so I was not a bit surprised when 80 people showed up for the co-ed shower. What a great group of people. We rented a building close to home and served lots of food and played games. I have to say that was my first co-ed baby shower and it was a good one! I’ve never seen so many gifts. They are truly blessed. As the shower was winding down I was not looking forward to the clean up as it had been a long day. All of a sudden everybody started bagging the trash, breaking down the tables, putting the folding chairs away and loading everything in the cars! They even grabbed the brooms and swept the entire room before I could pack up my stuff and the food. Done in 30 minutes – how cool is that?!?
Look at all these presents! My granddaughter is a lucky girl 🙂
Our daughter Allie made a diaper cake in the shape of a motorcycle for a gift – so cute!
Thanks so much for stopping by – hope you have a wonderful week.
Tricia
These sandwiches look great! I would take a sandwich like this over a bowl of soup any day! Portobellos have a bit of a meaty tasty and chew so I bet they are wonderful for a French Dip sandwich! What a storm of excitement in your life with the grandbabies due! The shower sounds like it was a huge success! Your daughter really should do a guest post on how to make that adorable motorcycle diaper “cake”!
Thanks Wendy! The shower was such fun – they have great friends. Won’t be long now!
Love using mushroom in vegetarian broths! They have so much flavor, and such a meaty flavor. One of my favorite tricks. BTW, there’s also a way of making a vegetarian French onion soup that’s really good — use miso when making the broth. I think I saw this originally on the NYT. Just an FYI. 🙂 Anyway, super recipe — thanks so much.
Thank you John – and my husband thanks you – I’ll look for it so he can have his french onion soup 🙂 Have a great week!
It is amazing how mushrooms can give the same rich flavor as beef. What a delicious-looking sandwich, Tricia! Most of our friends here do ‘couples’ showers, and two of my baby showers over 30 years ago were ‘couples’ showers. A great way to celebrate with good friends. What a bountiful shower it was!
I grew up with the old lady showers with corsages, butter mints and peanuts – so glad times have changed and the guys get to come. There were many men there by themselves and it was their first shower. Very neat! Thanks Susan.
You’ve improved on a classic. GREG
Thanks Greg – have a wonderful weekend!
Turning French dip into a vegetarian version , what a great idea . I love it!
80 people for a shower, that’s huge. I’m glad you didn’t have to do it all by yourself . Congratulations on your granddaughter.
Thanks Gerlinde! Have a great week!
When I first saw this picture I thought it was roast beef but love your vegetarian creation, Tricia! Now I can eat this twice a week guilt-free, lol.
So many delicious flavors in this comfort food. I’m going to leave the house in this blizzard to get the ingredients. So excited to taste this!
Your shower – wow! How fun that it was such a big success and then everyone helped clean up. Congratulations on the upcoming arrival of a new baby girl. How exciting for everyone!
Thanks Robyn – sorry about the blizzard – we are supposed to get a small amount of snow in a few days – you must be sending it our way. You’re going to love this sandwich – it completely satisfies without the beef!
wow…a girl…how exciting!! CONGRATULATIONS on new family member, Tricia.
That sounds like a perfectly delicious dip!
Thanks so much Angie – have a great week 🙂
I could sure go for this sandwich right now, I LOVE french dip sandwiches and this will be going on my must make list. I love mushrooms and onions!
Me too Diane. If you love mushrooms and onions you need to make this! Have a great week and thanks for stopping by.
Wow, Tricia! This looks and sounds superb! That shower seems over the top! Can’t wait to “meet” this new little one. You must be so excited!
We are very excited Abbe – thanks so much for stopping by!
Looks great! And all those beautiful gifts for such a special little girl♥
It is a special time for sure Monique – thanks for stopping by!
I love this sandwich and so would my husband and my vegetarian daughter!! 🙂 Going on the menu for this week, for sure. Love the shower photos. Looks like great fun and so wonderful to have really helpful guests 🙂
Sometimes it’s hard to get excited about meatless meals – but this one fully satisfies on many levels. Hope you love it as much as we do!
What a lovely shower you must have had and so nice for everyone to pitch in and help clean up!
And vegetarian French dip sandwich? That is genius! Why haven’t I ever thought of that. It looks incredible and such a nice lighter alternative. Wish I could have this for lunch today. : )
I just adore sandwiches that have a warm dip for added flavor and juiciness – this one is our new favorite! Have a great week and thanks for stopping by!
Wow, you’re a stronger woman than I am, I would have melted under the pressure 🙂 The French Dip looks so good to me right now, it’s 6pm and I haven’t the foggiest what we’re doing for dinner…wish I could reach right in….
I was very tired for sure Sue. Another shower coming up in a few weeks – no rest for the weary! I think I could put caramelized onions on anything and make a meal out of it. Have a great week!
Love your sandwich Tricia, it’s a brilliant idea and I don’t believe anyone would miss the meat! And the shower sounds delightful though you had to be quite tired when it was all done. I’m sure lots of wonderful memories were made!
Thanks Chris – we still love meat but know it’s better if we eat it occasionally instead of often. So happy to have recipes that fill the space in between with deliciousness!