Onion Burger

Prep the onions: Slice onions paper-thin using a mandoline or very sharp knife. You want translucent, nearly see-through slices. This is crucial for proper integration with the meat.

Portion the beef: Divide ground beef into 4 equal balls, about 4 oz each. Don't overwork the meat - just loosely form into balls.

Heat the griddle: Get a flat-top griddle or large cast iron skillet screaming hot. You want it around 400-450F. Lightly oil the surface.

Place the beef: Drop a beef ball onto the hot griddle. Immediately place a large handful of sliced onions (about 1/2 cup) directly on top of the beef.

The smash: Using a heavy spatula or burger press, smash down HARD on the onions and beef together. Press until the patty is paper-thin (about 1/4 inch) and the onions are embedded into the meat. Season with salt and pepper.

Cook the first side: Let cook undisturbed for 2-3 minutes. The edges should get lacy and crispy. The onions will caramelize into the meat, creating an incredible aroma.

Flip carefully: Slide the spatula under the entire patty and flip. The onion side is now on the griddle. Cook another 2 minutes. Add cheese now if using.

Toast the buns: Toast bun halves on the griddle cut-side down until lightly golden, about 30 seconds to 1 minute.

Assemble: Spread mustard on both bun halves. Place pickle slices on the bottom bun. Add the patty with the onion-side up so you can see those beautiful caramelized strands. Top with bun.

Serve immediately: Serve right away while hot and crispy. The contrast between the soft bun, crispy-edged patty, and sweet caramelized onions is what makes this burger legendary!