Jalapeño-Onion Smash Burgers (Print Version)

# Ingredients:

→ For the Burger Sauce

01 - 3 tablespoons mayonnaise
02 - 1 1/2 tablespoons ketchup
03 - 1 teaspoon Worcestershire sauce
04 - 1/2 teaspoon black pepper
05 - 1/4 teaspoon garlic powder
06 - 1/4 teaspoon kosher salt

→ For the Smash Burgers

07 - 1 1/2 pounds 80% lean ground beef
08 - 1 teaspoon canola oil
09 - 1 large yellow onion, thinly sliced (approximately 2 cups)
10 - 1 large jalapeño chile, thinly sliced (approximately 1/2 cup)
11 - 1 1/4 teaspoons kosher salt, divided
12 - 3/4 teaspoon black pepper, divided
13 - 4 slices American cheese
14 - 4 hamburger buns, split and toasted

# Instructions:

01 - In a small bowl, combine mayonnaise, ketchup, Worcestershire sauce, black pepper, garlic powder, and kosher salt. Mix well, cover, and refrigerate until ready to use.
02 - Heat a large cast-iron skillet over medium heat and add the canola oil. Add the sliced onions and jalapeños to the skillet. Season with 1/4 teaspoon kosher salt and 1/4 teaspoon black pepper. Cook, stirring occasionally, until the onions are caramelized and the jalapeños are softened, about 10-15 minutes. Transfer to a bowl and set aside.
03 - Divide the ground beef into 8 equal portions (approximately 3 ounces each). Gently form each portion into a loose ball; avoid overworking the meat to maintain tenderness. Place the balls on a parchment-lined baking sheet and refrigerate until ready to cook.
04 - Wipe the skillet clean and return it to high heat until it begins to smoke slightly. Place a few beef balls into the hot skillet, ensuring not to overcrowd. Using a sturdy spatula or a burger press, firmly press down each ball to flatten it into a thin patty. Season the patties with a pinch of the remaining kosher salt and black pepper. Cook until the edges are crispy and the center is cooked through, about 2-3 minutes per side. During the last minute of cooking, place a slice of American cheese on each patty to melt.
05 - Spread a generous amount of the prepared burger sauce on the cut sides of the toasted hamburger buns. Place a cheese-topped patty on the bottom bun. Top with a spoonful of the caramelized onion and jalapeño mixture. Add any additional desired toppings. Cover with the top bun and serve immediately.

# Notes:

01 - For less heat, remove the seeds and membranes from the jalapeños before slicing.
02 - To achieve the best crust on the burgers, ensure the skillet is very hot before adding the beef.
03 - These burgers pair well with classic sides like fries or a simple salad.