Crunchy French Onion Chicken

Don’t settle for any old burger. These thick pub burgers are loaded with beer-braised mushrooms, cheddar, and a swipe of garlicky mayonnaise.

ingredient

Garlic Mayonnaise

1/3 cup mayonnaise
1 tablespoon whole-grain mustard
1/2 teaspoon soy sauce
1 large garlic clove, grated (about 1/2 teaspoon)

Drunken Mushrooms

3 tablespoons olive oil
8 ounces cremini mushrooms, thinly sliced
1 small shallot, chopped (about 1/4 cup)
1 teaspoon chopped fresh thyme
1/4 teaspoon kosher salt, plus more to taste
1/4 teaspoon black pepper
1/2 cup light lager beer

Tavern Burgers

2 pounds high-quality 80% lean ground beef
2 teaspoons kosher salt
1 1/4 teaspoons black pepper
4 extra-sharp white cheddar cheese slices
2 tablespoons unsalted butter, softened
4 sesame seed hamburger buns, split
Butter lettuce, sliced red onion, Drunken Mushrooms, and bread-and-butter pickle chips, for serving

Directions

Stir together mayonnaise, mustard, soy sauce, and garlic in a small bowl. Cover, and chill until ready to serve.
Heat oil in a large skillet over medium-high. Add mushrooms, spreading in an even layer, and cook, undisturbed, until well browned, about 8 minutes. Stir mushrooms, and continue cooking, stirring occasionally, until tender and browned, 2 to 4 minutes. Reduce heat to medium, and add shallot, thyme, salt, and pepper; cook, stirring often, for 1 minute. Add beer; cook, stirring occasionally, until liquid is completely reduced, 3 to 4 minutes. Season with additional salt to taste.
Divide beef into 4 (8-ounce) portions. Working with 1 portion at a time, shape into a loose ball. Flatten ball between your palms to form a 4 1/2-inch-wide patty (about 1 inch thick). Press your thumbs into the center of the patty to create an indentation (about 1/2 inch deep). Transfer patty to a parchment paper–lined baking sheet; repeat process with remaining beef portions. Cover, and chill while preparing grill.
Preheat grill to medium (350°F to 400°F); place a large cast-iron skillet or griddle on grill to preheat. (Alternatively, heat a large cast-iron skillet or griddle on the stove over medium.) Remove patties from refrigerator, and sprinkle evenly with salt and pepper; place patties in skillet, spacing at least 1 inch apart. Cook, undisturbed, until patties have formed a deep golden brown crust on the bottom, 6 to 7 minutes. Flip patties; cook, undisturbed, until patties are well browned on both sides and a meat thermometer inserted into center of patty registers 118°F, about 3 minutes.
Place 1 cheddar slice on each patty. Cover skillet with a baking sheet, and let stand just until cheddar is melted, about 1 minute. Uncover skillet, and transfer patties to baking sheet to rest for 5 minutes. Do not wipe skillet clean.
Meanwhile, spread butter evenly on cut sides of hamburger buns. Working in batches, toast buns in beef drippings in skillet over medium until golden brown, about 1 minute.
Spread garlic mayonnaise on cut sides of buns. Top bottom buns with lettuce, red onions, patties, drunken mushrooms, and pickle chips. Sandwich with top buns, and serve immediately.