These Portobello Mushroom Burgers are absolutely bursting with flavour! With a simple 4 ingredient marinade, these are sure to be some of the best veggie burgers you’ve ever had!
Portobello mushrooms make perfect burgers for a couple of reasons. Firstly, they’re big and juicy. I don’t know about you, but when someone says ‘mushroom burger’ I always think ‘it better be a darn big mushroom otherwise this ain’t gonna work.’ Portobellos can hold their own in a bun, trust me. Second is that they take on flavour so well.
Portobello Mushroom Burger Marinade
The absolute key to a delicious mushroom burger is to marinate the mushrooms. Because portobellos are so large, you really want to inject as much flavour into them as possible, just to ensure you don’t end up with a bland mushroom burger. The mushroom is the star of the show after all. Here’s what you’ll need for the marinade:
Portobello Mushroom Marinade
- Balsamic Vinegar
- Soy Sauce
- Worcestershire Sauce
The combination of balsamic vinegar and soy sauce works wonders on so many things, not just including burgers. With the addition of Worcestershire sauce, you get a really deep ‘beefy’ and delicious flavour. And garlic? Who doesn’t want garlic with their mushrooms.
Alongside the fantastic 4, you’ll just need a swig of olive oil (just to help with the frying) and a pinch of salt and pepper (to taste).
How long to marinate for?
I find the sweet spot lies between 30mins – 1hour. Any less and there isn’t enough time for the mushrooms to soak up the goodness, any more and the mushrooms start to wilt and shrink from the acidity.
Process shots: remove stalks (photo 1), combine marinade in zip lock bag (photo 2), add mushrooms (photo 3), marinate (photo 4).
How to Make Portobello Mushroom Burgers
These beauties are perfect for the BBQ, but we’re in the thick of winter now so pan frying is where we’re at. I don’t recommend baking these as you won’t get the same caramelization and therefore, they’ll be laking in flavour. When it comes to the toppings, here’s the usual suspects for me:
- Toasted Buns – Important to toast the buns, just so they give a nice crispy contrast to the soft mushroom in the centre.
- Hummus – Don’t skip this, even if it’s store bought!
- Caramelized Onions – Below I’ll show a shortcut to caramelized onion, you can also sub sliced red onion if you wish.
- Cheese – Here I use Swiss which works nicely. Use cheese of choice though!
- Tomato – One hefty slice of beef tomato will do the trick.
- Watercress – Or greens of choice.
A lot of the juices stay in the pan after you’ve fried the mushrooms, the onions will soak this up and taste beyond delicious once they’re fried. For proper caramelized onions, you want to fry them low and slow, but here I make quick caramelized onions (with a little help from a tsp of brown sugar).
Process shots: Add your mushrooms face down to a pan over medium heat and fry for 4-5mins until soft (photo 1), flip mushrooms over (photo 2), add cheese and fry for another 4-5mins or until knife tender with the cheese melted. Remove from pan (photo 3), add onions & sugar and continue to fry until soft and caramelized (photo 4).
What to serve with Portobello Mushroom Burgers?
If you’re looking for another awesome marinated mushroom recipe be sure to check out my Crispy Breaded Mushrooms!
For more similar recipes give these a ganders too:
Delicious Burger Recipes
Alrighty, let’s tuck into the full recipe for these mushroom burgers shall we?!
How to make Portobello Mushroom Burgers (Full Recipe & Video)
Portobello Mushroom Burgers
- Large Zip Lock Bag
- Frying Pan & Tongs
- Sharp Knife & Chopping Board
- Paper Towels (for cleaning mushrooms)
Ingredients (check list):
- 4 Portobello Mushrooms, stalks removed & cleaned with damp paper towel
- 2 tbsp Soy Sauce
- 1 tbsp Balsamic Vinegar
- 1 tbsp Worcestershire Sauce
- 1 tsp Garlic
- 1 tbsp Olive Oil
- Salt & Black Pepper, to taste
- 4 Burger Buns, toasted
- 4 slices of Tomato
- 4 tbsp Hummus
- 4 slices of Cheese, here I use Swiss
- 1 large Red Onion
- 1 tsp Brown Sugar
- 1 handful Watercress
- In a zip lock bag, combine your mushrooms with the marinade. Mix it around so all of the mushrooms are coated, then allow to marinate for 30mins - 1 hour, or as long as you have time for. I wouldn't go past 1 hour because they start to shrink from the acidity. Even 5mins makes the world of difference.
- Place your mushrooms facing down on a pan over medium heat and fry 4-5mins. Flip, then top with cheese and fry for another 5mins or until tender. Timings will depend on the size and shape of your mushrooms.
- Remove from pan, leaving any leftover juice, then add your onions. Fry until soft, then add sugar and continue frying until caramelised. For the best caramelised onions you want to fry low over a long period of time to release their natural sugars, but for convenience this works just fine!
- Top your bottom burger bun with hummus, then watercress, then tomato, next with your mushroom burger, topped with your onions and finished with the top bun. Enjoy!
Quick 1 min demo!
If you loved this Mushroom Burger Recipe then be sure to Pin it for later! Already made it or got a burning question? Give me a shout in the comments below and pick up your free ecookbook along the way!