French Onion Burger with Truffle Mayo
Servings: 6
INGREDIENTS
2 lbs ground beef, divided into 6 patties
Salt and pepper to taste
1 tbsp canola oil
Caramelized onions:
8 medium onions, sliced
3 tbsp olive oil
1 tbsp butter
1 tsp sherry vinegar
1 tsp worcestershire sauce
Truffle mayo:
1 ½ cups mayo
1 ½ tsp truffle paste (or truffle oil)
To build:
6 brioche buns, toasted
120 g gruyere cheese, sliced
2 cups arugula
PREPARATION
1. Begin by dividing your beef into 6 patties, each about ½” thick. Allow the beef to come up to room temperature while you make your caramelized onions. To cook the onions, add the olive oil and butter to a large pot and heat over medium low. When melted, add the onions and season with a generous pinch of salt and pepper. Cook, stirring occasionally for 60 - 70 minutes until the onions have caramelized, being sure to maintain a low and gentle heat. Deglaze the bottom of the pot by stirring in the sherry vinegar and worchestire sauce, then set aside. These onions can be made the day before.
2. To cook the burgers, add the canola oil to a cast-iron pan and heat over medium. Then season the burgers with salt and pepper and add to the cast-iron, working in batches to avoid over- crowding. Cook the burgers, undisturbed, for 3-4 minutes then flip and cook for another 2-3 minutes. Remove and top each burger with some of the caramelized onions and some sliced gruyere.
3. Place the burgers under the broiler and allow the cheese to melt for 1 - 2 minutes. To build the burger, toast your buns and spread each side with truffle mayo. Add the arugula to the bottom bun, followed by the onion and gruyere topped burger, before adding the top bun. Enjoy!