A burger so good, you wouldn’t even know it’s vegan! Portobello mushrooms are marinated in a savory sauce, then sauteed until soft. Balsamic portobello burgers are topped with caramelized onions, fresh tomato, and slathered in vegan aioli.

A burger so good, you wouldn't even know it's vegan! Portobello mushrooms are marinated in a savory sauce, then sauteed until soft. Balsamic portobello burgers are topped with caramelized onions, fresh tomato, and slathered in vegan aioli.

It’s always nice to switch up your traditional burger. Take a break from a beef patty and try these delicious portobello burgers! The portobellos are marinated in a savory sauce and cook very fast on the stovetop, no grill required.

What you’ll need to make Balsamic Portobello Burgers

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A burger so good, you wouldn't even know it's vegan! Portobello mushrooms are marinated in a savory sauce, then sauteed until soft. Balsamic portobello burgers are topped with caramelized onions, fresh tomato, and slathered in vegan aioli.

How to make portobello burgers

Marinate the portobello mushrooms

First, you’ll whisk up the marinade made with olive oil, balsamic vinegar, Italian seasoning, and garlic. Let them sit while you prepare the sweet potatoes. The marinade will infuse the mushrooms with a delicious flavor. After they’ve marinated for a while, you’ll sautee them over medium heat until they soften and shrink up a bit. 

Caramelize the onions

This is an important step, and it’s vital that you take the time to do it correctly! It’s simple though — it’s cooking sliced onions with oil on low heat until they get super soft and golden. Caramelizing the onions takes away the bitterness of raw onion and adds a delicious sweetness to the burger.

Whisk the vegan aioli

The vegan aioli is simply vegan mayonnaise (I like Follow Your Heart), oil, Dijon, and spices. You’ll slather this on the buns before adding the rest of the ingredients. 

A burger so good, you wouldn't even know it's vegan! Portobello mushrooms are marinated in a savory sauce, then sauteed until soft. Balsamic portobello burgers are topped with caramelized onions, fresh tomato, and slathered in vegan aioli.

To build your burger, spread the vegan aioli over the buns. Top with lettuce and tomato, portobello, and caramelized onions. Serve with a side of roasted sweet potatoes!

Here’s the recipe for Balsamic Portobello Burgers with Caramelized Onions & Roasted Sweet Potatoes: 

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Balsamic Portobello Burgers with Caramelized Onions & Roasted Sweet Potatoes


  • Author: Emily Weeks, RDN, LD
  • Prep Time: 15 minutes
  • Cook Time: 30 minutes
  • Total Time: 45 minutes
  • Yield: Makes 2 burgers 1x

Description

A burger so good, you wouldn’t even know it’s vegan! Portobello mushrooms are marinated in a savory sauce, then sauteed until soft. Balsamic portobello burgers are topped with caramelized onions, fresh tomato, and slathered in vegan aioli.


Scale

Ingredients

  • 1 lb sweet potato
  • 1 tsp extra virgin olive oil
  • ½ tsp paprika
  • ½ tsp salt
  • ¼ tsp black pepper
  • 2 caps portobello mushrooms
  • 2 cloves garlic
  • 2 tbsp extra virgin olive oil
  • 2 tbsp balsamic vinegar
  • 1 tsp Italian seasoning
  • 1 medium yellow onion
  • 1 tbsp extra virgin olive oil
  • ¼ tsp salt
  • 2 tbsp vegan mayonnaise
  • 1 tsp extra virgin olive oil
  • ½ tsp Dijon mustard
  • ¼ tsp garlic powder
  • ¼ tsp salt
  • ½ head butter (Boston) lettuce
  • 1 tomato
  • 2 whole grain buns or rolls

Instructions

  1. Preheat oven to 400°F.
  2. Peel the sweet potatoes and cut into 1-inch pieces. Transfer to a large bowl; add 1 tsp oil, paprika, salt, and pepper, toss to coat. Add potatoes to a baking sheet and bake, until softened, about 20-25 minutes. Reserve bowl for later use.
  3. Dry the mushrooms; remove the stems and carefully scrape out the gills. Peel and mince the garlic.
  4. In the large bowl, whisk together the 2 Tbsp oil, vinegar, Italian seasoning, and garlic. Add the mushrooms and toss to coat; set aside.
  5. Peel and slice the onion into half rings.
  6. Heat a medium saucepan over medium heat. Once the saucepan is hot, add 1 Tbsp oil and swirl to coat the bottom. Add the onion and salt to the saucepan; cook, stirring occasionally, until browned and softened, 15-20 minutes.
  7. In a medium bowl, whisk together the mayonnaise, olive oil, Dijon, garlic powder, and salt. Set aside.
  8. Preheat a skillet over medium-high heat. Once the skillet is hot, add the mushrooms. Cook, stirring occasionally, until softened, 3-5 minutes per side. Discard leftover marinade.
  9. Separate the lettuce head into leaves. Slice the tomato.
  10. To serve, spread the mayonnaise mixture on buns. Top with tomato slices, lettuce, mushrooms and caramelized onions. Serve the roasted sweet potatoes on the side. Enjoy!

A burger so good, you wouldn't even know it's vegan! Portobello mushrooms are marinated in a savory sauce, then sauteed until soft. Balsamic portobello burgers are topped with caramelized onions, fresh tomato, and slathered in vegan aioli.