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 ground beef (80% lean, high-quality)
08 - 1 teaspoon canola oil
09 - 1 large yellow onion, thinly sliced (about 2 cups)
10 - 1 large jalapeño chile, thinly sliced (about 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 - Combine mayonnaise, ketchup, Worcestershire sauce, black pepper, garlic powder, and kosher salt in a small bowl. Mix well, cover, and refrigerate until ready to use.
02 - Heat a large cast-iron skillet over medium heat and add canola oil. Add sliced onions and jalapeños. Season with 1/4 teaspoon kosher salt and 1/4 teaspoon black pepper. Cook, stirring occasionally, until onions are caramelized and jalapeños softened, about 10-15 minutes. Transfer to a bowl and set aside.
03 - Divide ground beef into 8 equal portions (approximately 3 ounces each). Gently form each portion into a loose ball without overworking the meat to maintain tenderness. Place balls on a parchment-lined baking sheet and refrigerate until ready to cook.
04 - Wipe the skillet clean and heat on high until slightly smoking. Place a few beef balls into the hot skillet without overcrowding. Use a sturdy spatula or burger press to flatten each ball into a thin patty. Season patties with a pinch of remaining kosher salt and black pepper. Cook until edges are crispy and center 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 prepared burger sauce on the cut sides of toasted buns. Place a cheese-topped patty on the bottom bun. Top with caramelized onion and jalapeño mixture, followed by additional toppings if desired. 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.