Gourmet Mushroom Gruyère Cheeseburger With Truffle Aioli

For the Burgers:

• 5 tablespoons butter, divided

• 1 small onion, thinly sliced

• 2 teaspoons salt, divided

• 2 cups mushrooms, sliced

• 1 teaspoon Cajun Power Worcestershire sauce

• 1/2 teaspoon dried thyme

• 4 brioche burger buns

• 4 (3-ounce) ground beef burger patties

• 1 teaspoon ground black pepper

• 1 cup Gruyère, shredded

For the Truffle Aioli:

• 1/2 cup mayonnaise

• 1 teaspoon salt

• 1/2 teaspoon ground black pepper

• 1 teaspoon lemon juice

• 1/2 teaspoon NOLA Blends White Truffle Oil or Black Truffle Oil

• 1 garlic clove

Directions:

Make the Caramelized Onion & Mushrooms 

1. Start by preparing the mushroom and onions. Heat a sauté pan on medium-high heat. Add 3 tablespoons of the butter, sliced onion, and 1 teaspoon of the salt. Sauté for 5 minutes, stirring frequently, until the onion becomes softened and slightly browned.
   
   
2. Push the onion to one side of the pan and add the mushrooms. Sauté until the mushrooms are browned and the onion is even softer, about 3 minutes.
   
   
3. Add the Worcestershire sauce and dried thyme and toss to combine. Cook for another minute and then remove from the heat and set aside. 

Toast the Buns

1. Heat a cast-iron pan on medium-high heat. Add the remaining 2 tablespoons of butter. Once melted, add the buns to the pan cut-side down and toast them until they are golden brown. You will have to toast them in 2 batches.

Start the Burgers

1. Salt and pepper both sides of the burgers with the remaining 1 teaspoon salt and all of the pepper. Keeping the pan at medium-high, cook the burgers for about 5 minutes per side until browned on both sides for medium doneness.

Make the Truffle Aioli

1. While the burgers are cooking, gather the ingredients for the truffle aioli.

2. Whisk together the mayo, salt, pepper, lemon juice, and truffle oil. Grate the garlic into the mixture using a Microplane grater (or finely mince it) and whisk to combine.

Assemble the Burgers

1. During the last minute or two of cooking, sprinkle the tops of the burgers with some of the shredded cheese. Then divide the mushroom mixture among the 4 burgers and then top with the remaining shredded cheese. Cover the pan with a lid and cook for the remaining 1 or 2 minutes to allow the cheese to melt.
   
   
2. Slather the bun with the aioli.
   
   
3. Top the bun with the mushroom and cheese-coated burger and dig in.