West Coast Style Double Smashburger
A classic copycat of the iconic West Coast drive-thru double cheeseburger, featuring crispy lacy-edged smashed beef patties, melty American cheese, sweet grilled onions, crisp lettuce, fresh tomato, and a secret tangy spread, all on a toasted bun.
Equipment
- Large cast iron skillet or flat top griddle
- Stiff metal spatula (no slots)
- Parchment paper (cut into 4x4 inch squares)
- Small mixing bowl
- Cutting board
- Chef's knife
Ingredients
Secret Tangy Sauce
- 0.25 cup Mayonnaise — Full fat preferred
- 2 tablespoons Ketchup
- 1.5 tablespoons Sweet pickle relish
- 0.5 teaspoon White vinegar
- 0.5 teaspoon Granulated sugar
Patties & Seasoning
- 8 ounces Ground beef (80/20 chuck) — Divided into four 2-ounce portions, loosely rolled into balls
- 1 teaspoon Kosher salt — Mixed with black pepper and garlic powder
- 0.5 teaspoon Black pepper — Freshly ground
- 0.5 teaspoon Garlic powder
- 4 slices American cheese — Classic processed cheese for the best melt
Buns & Toppings
- 2 whole Hamburger buns — Soft white buns, plain or sponge dough
- 1 tablespoon Unsalted butter — Softened, for toasting buns
- 0.5 cup Yellow onion — Finely diced
- 1 teaspoon Vegetable oil — For the pan
- 2 leaves Iceberg lettuce — Torn to bun size
- 2 slices Tomato — Thickly sliced
Secret Tangy Sauce
| 0.25 cup | Mayonnaise | Full fat preferred |
| 2 tablespoons | Ketchup | |
| 1.5 tablespoons | Sweet pickle relish | |
| 0.5 teaspoon | White vinegar | |
| 0.5 teaspoon | Granulated sugar |
Patties & Seasoning
| 8 ounces | Ground beef (80/20 chuck) | Divided into four 2-ounce portions, loosely rolled into balls |
| 1 teaspoon | Kosher salt | Mixed with black pepper and garlic powder |
| 0.5 teaspoon | Black pepper | Freshly ground |
| 0.5 teaspoon | Garlic powder | |
| 4 slices | American cheese | Classic processed cheese for the best melt |
Buns & Toppings
| 2 whole | Hamburger buns | Soft white buns, plain or sponge dough |
| 1 tablespoon | Unsalted butter | Softened, for toasting buns |
| 0.5 cup | Yellow onion | Finely diced |
| 1 teaspoon | Vegetable oil | For the pan |
| 2 leaves | Iceberg lettuce | Torn to bun size |
| 2 slices | Tomato | Thickly sliced |
Instructions
-
In a small bowl, whisk together the mayonnaise, ketchup, sweet pickle relish, white vinegar, and sugar. Cover and refrigerate to let the flavors meld while you prepare the rest of the ingredients.
~5 minMaking the sauce ahead of time (even the day before) drastically improves the flavor. -
In a small bowl, mix together the kosher salt, black pepper, and garlic powder to create your seasoning blend. Set aside.
~1 min -
Heat a large cast iron skillet over medium heat. Butter the cut sides of the hamburger buns and place them face-down in the skillet. Toast until golden brown and crispy, about 2 minutes. Remove and set aside.
~3 minWatch the buns closely as they can go from perfectly toasted to burnt very quickly. -
Increase the heat to medium-high. Add the vegetable oil and finely diced onions to the skillet. Cook, stirring frequently, until the onions are deeply browned and caramelized, about 5-7 minutes. Remove from the skillet and wipe the skillet mostly clean with a paper towel, leaving a light sheen of oil.
~7 minFor true fast-food style, chop the onions very finely so they melt into the cheese later. -
Increase the heat under the cast iron skillet to high until it is screaming hot and lightly smoking. Place two of the loosely formed 2-ounce meatball portions into the skillet, leaving plenty of space between them.
~1 minDo not pack the meat tightly when forming the balls; keep them loose for better texture. -
Immediately place a square of parchment paper over a meatball. Use a stiff metal spatula (pressing down with another heavy object like a meat press or a wooden spoon handle if needed) to firmly smash the patty flat against the skillet. Flatten it until it is very thin, slightly wider than the bun. Repeat with the second patty. Discard the parchment squares.
~1 minThe parchment paper prevents the meat from sticking to the spatula during the smash. -
Generously season the top of each smashed patty with the prepared seasoning blend. Let cook undisturbed for about 60 to 90 seconds. You should see juices bubbling up and the edges becoming deeply browned, crispy, and lacy.
~2 min -
Using the stiff metal spatula, forcefully scrape under the patties to keep the crust intact, and flip them. Top each patty immediately with a portion of the grilled onions, followed by a slice of American cheese. Cook for another 30-45 seconds until the cheese is completely melted.
~1 minStack one patty on top of the other in the pan to fuse the cheese and meat together. -
Assemble the burgers: Spread a generous tablespoon of the secret sauce on the toasted bottom buns. Top with fresh sliced tomato, then iceberg lettuce. Place the double patty stack on top of the lettuce, and cover with the top bun. Serve immediately.
~2 minPutting the tomato and lettuce under the meat mimics the famous West Coast drive-thru build.
Tips & Storage
- Ensure your skillet is smoking hot before adding the beef. This is critical for the Maillard reaction that creates the iconic crust.
- Use 80/20 ground chuck. Leaner meat will dry out and won't develop the right crust.
- Do not move the patties once smashed until it is time to flip. Patience creates the crust.
- Storage: Best enjoyed immediately. Leftover cooked patties can be stored in an airtight container in the refrigerator for up to 3 days and reheated in a skillet or microwave, though the crispy edges will soften.