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    Home » Meat » Beef

    Mushroom Burgers with Caramelized Onions

    Published: Jul 26, 2020 · Modified: Oct 19, 2023 by Amy Sandidge · This post may contain affiliate links · 3 Comments

    Jump to Recipe

    These mushroom burgers with caramelized onions gave me all the feels!I haven't had a big fat burger in a while, not cutting out meat or anything, but for some reason, some time has passed since I enjoyed one. So how about a big beef burger, caramelized onions, the mushrooms all topped with a rosemary and black pepper mayo artisan bun? Yum, yum, and yum!

    I normally just do a plain beef burger, topped with just about everything I can add to it. This burger was born from a collaboration on Instagram featuring... you guessed it, mushrooms.

    Preparing the mushrooms and onions

    So, start this burger with your these lovely little fungi. I used a simple white mushroom, bought in the bulk at Costco. Slice the mushrooms for sauteing.

    woman slicing with mushrooms with a chefs knife on a white cutting board

    While I was slicing the mushrooms, I felt like caramelized mushrooms would need a place on these burgers too. They were sliced at the same time.

    woman slicing onions on a white cutting board with a chef's knife

    Add the mushrooms to a hot pan with a little olive oil. I also sprinkle with salt and add a little minced garlic. Mix these occasionally. They will cook and begin to shrink substantially within 5 minutes.

    sauteing mushrooms in a small nonstick pan

    I had the onions caramelizing at the same time too. Caramelize them on a medium-low for at least 15-20 minutes.

    caramelizing onions in a small nonstick pan

    Rosemary and black pepper mayo

    Now, on to your rosemary black pepper mayo. It's simple. Add your mayo, rosemary, black pepper and lemon juice to a small bowl and mix.

    woman mixing rosemary into mayonnaise

    The burger

    Everything else is ready, so not let's get those burgers started!

    woman sprinkling burger with seasoning

    You can grill your burgers, but I love to do mine in a cast iron skillet. Lodge is my favorite!

    cooking beef burgers in a cast iron skillet

    Assembling the mushroom burgers with caramelized onions

    Time to assemble!! I bought the artisan rolls at Costco. If you want to make your own, that's great! Add the burgers.

    woman add burgers with melted swiss onto artisan bun

    Layer on those caramelized onions.

    woman adding caramelized onions onto burger with swiss

    Pile on those mushrooms! I promise you, they make the burger!

    woman adding sautted mushrooms onto beef burger.

    You can add the mayo on the top or bottom. I added mine on the top!

    woman spreading aioli onto burger bun

    Top it off and it's done!

    woman preparing a mushroom burger with caramelized onions

    This burger is huge. It's intense. It isn't for every day, but it is so good when it does happen.

    mushroom burger with caramelized onions

    Other options

    While I love these mushroom burgers with caramelized onions are amazing, I realize they are not for everyone. If you are looking for a lighter option? What about these teriyaki chicken burgers? Or if beef isn't your thing, what about these black bean burgers?

    mushroom burger with caramelized onions

    Mushroom burgers with caramelized onions.

    Amy Sandidge
    If you are looking for the best burger, this is your recipe. The combination of the beef, mushrooms, and caramelized onions is the best!!
    5 from 1 vote
    Print Recipe Pin Recipe
    Prep Time 40 minutes mins
    Total Time 40 minutes mins
    Course Main Course
    Cuisine American
    Servings 4

    Ingredients
      

    Caramelized Onions

    • 3 cups onions, sliced
    • 2 teaspoons olive oil
    • ¼ teaspoon salt

    Rosemary and Pepper Aioli

    • ⅓ cup mayo
    • 1 teaspoon rosemary
    • ½ teaspoon ground black pepper
    • 1 teaspoon lemon juice
    • salt to taste

    Sauteed Mushrooms

    • 5 cups sliced mushrooms
    • 1 tablespoon olive oil
    • ½ teaspoon salt

    Burgers

    • 1- ½ pounds ground beef
    • 2 tablespoons salt
    • 1 teaspoon ground black pepper
    • ½ teaspoon paprika
    • ½ teaspoon cayenne
    • 1 teaspoon garlic powder
    • 4 hamburger buns
    • 4 slices swiss cheese

    Instructions
     

    Caramelized onions

    • There are a few things that will need to happen at the same time, but in this recipe, let me tell you how I do it. Start with the onions, as they will take the longest.
    • Heat a nonstick skillet over medium heat. Add olive oil and heat. Add in onions and turn heat to medium-low. Add salt. Saute, stirring occasionally until the onions have turned a deeper caramel color. This will take a while, so be patient. It will probably take at least 20-25 minutes. You can use them right away or even store them in an airtight container in the fridge for up to 4 days.

    Aoili

    • Mix all ingredients for the aioli while the mushrooms and cooking. Taste and check for salt. Add it as needed.

    Burgers and Shrooms

    • While the onions are cooking, prep the mushrooms and the burgers.
    • Mix the seasoning for the burgers. Form 4 patties and season them with the seasoning,
    • Heat nonstick or cast-iron skillet over medium heat. Add olive oil and heat. Next add in mushrooms, salt, and garlic. Cook, stirring occasionally until the mushrooms are tender and have shrunk. Mine took about 5 minutes.I prefer to use my mushrooms right away. They can be stored in an airtight container for up to 2 days if you need to.
    • Now, heat your grill or cast-iron skillet as I did. You will want it pretty hot before you add the burgers.
    • Once it is heated, add the burgers. Cook for about 3-6 minutes per side, depending on how you take your burger.
    • Next, assemble the burgers. Add the burger to your bun, then the mushrooms, onions, and swiss cheese.
    • Last, slather with the aioli!
    • You are done. Sit back and enjoy. You deserve it!
    Keyword beef, mushrooms, onions
    Tried this recipe?Let us know how it was!
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    Reader Interactions

    Comments

      5 from 1 vote

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      Recipe Rating




    1. Brooke says

      August 02, 2020 at 4:02 am

      5 stars
      You had me at burgers but man, those onions and mushrooms realllllyyyy got me!

      Reply
      • admin says

        August 07, 2020 at 8:24 pm

        Oh, yes. One of our favorite burgers!! Thanks Brooke!

        Reply

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    Hi, I'm Amy! I am a culinary school graduate creating a comprehensive collection of recipes, with a focus on incorporating whole grains. My goal is to craft dishes that resonate with the whole family. 

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