Add all ingredients to a small bowl and stir to combine. Cover and refrigerate.
For the Smash Burgers:
Cut a piece of parchment paper to about a 5-inch square.
Divide the ground beef into 8 equal portions and roll each into a ball (don’t worry about making them perfect balls, we’re going to smash them!).
Preheat a large cast-iron skillet or griddle over high heat. Once it’s screaming hot, brush on the beef tallow or other fat (you can skip this if your pan is well-seasoned). Add 1 or 2 balls of meat on opposite sides of the skillet, leaving space for you to smash them (don’t crowd the pan).
Put the piece of parchment paper on top of a ball of meat, and use your press to smash the meat down to a patty about 1/4-inch thick. Peel off the parchment paper, and season the burger with salt and pepper.
Let the burger cook until it has a golden brown crust on the first side, about 2 minutes. Use a thin metal spatula to scrape under the burger, and then flip it. Cook the burger until golden brown on the second side, about 1 minute. Add the cheese during the last 30 seconds.
Transfer the burger to a plate and tent a piece of foil on top to keep it warm.
Cook the remaining burgers the same way.
To Serve:
Split a bun in half and top the bottom half of the bun with 2 cheeseburgers, 4 pickle chips, 1 onion slice, 1 tomato slice, 1 lettuce leaf, about 1 tablespoon of Smashburger Sauce, and the top half of the bun.
Notes
Storage:You can store leftover cooked burgers covered in the fridge for up to 4 days. However, this Smash Burgers recipe cooks up fast and these burgers are best when they’re eaten fresh while they’re still hot! If possible, make them right before you want to eat them.
How to Prevent the Press From Sticking to the Meat: Put a square of parchment paper on top of the meat before you press it down with the burger press.
To Toast the Buns: After cooking the burgers, add the buns (cut side of the bun facing down) to the hot skillet with the burger drippings, and toast until golden. Stay with it, this happens fast!
Ventilation: These burgers have a high fat content, and the kitchen has a tendency to get quite smoky when you make them, so be prepared! Turn on the kitchen vent, open a window, set up a griddle to cook outside, or do what you have to do.