Jul 13 2026
RestaurantsBecky's DinerMushroom Burger With Sauteed Mushrooms, Caramelized Onions, Swiss Cheese & Truffle Aioli Recipe

Mushroom Burger With Sauteed Mushrooms, Caramelized Onions, Swiss Cheese & Truffle Aioli Recipe

Inspired by Becky's Diner
Time45m
Serves4

Indulge in our decadent Mushroom Burger, featuring a juicy patty topped with a generous layer of sautéed mushrooms and sweet caramelized onions. Melted Swiss cheese adds a creamy richness, while our luxurious truffle aioli brings an irresistible earthiness to each bite. Served on a toasted bun, this gourmet delight is a must-try for any burger lover!

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Ingredients

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Burger Ingredients

Sautéed Mushrooms

Caramelized Onions

Method

Sautéed Mushrooms

  1. 1

    Prepare the Sautéed Mushrooms

    In a skillet over medium heat, add olive oil. Once hot, add minced garlic and sauté for 30 seconds until fragrant. Add the button mushrooms, salt, and black pepper. Cook until mushrooms are browned and tender, about 5-7 minutes. Set aside.

Caramelized Onions

  1. 2

    Caramelize the Onions

    In the same skillet, add butter and sliced onions. Cook on low heat, stirring occasionally, until the onions are soft and caramelized, about 15-20 minutes. Add brown sugar and salt during the last 5 minutes of cooking. Set aside.

Truffle Aioli

  1. 3

    Make the Truffle Aioli

    In a bowl, mix mayonnaise, truffle oil, lemon juice, garlic powder, and salt. Adjust seasoning according to taste. Refrigerate until ready to use.

Assemble the Burger

  1. 4

    Grill Portobello Mushrooms

    Preheat the grill to medium-high heat. Brush portobello mushrooms with olive oil and grill for about 5-7 minutes on each side, or until tender.

  2. 5

    Assemble the Burger

    On the bottom half of each burger bun, place a grilled portobello mushroom, top with sautéed mushrooms, caramelized onions, and a slice of Swiss cheese. Spread truffle aioli on the top half of the bun and place it on top to complete the burger.

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