Smash Burger Fries Recipe

Prep and par-cook

Cut each scrubbed russet potato into 1/3–1/2-inch fries. Rinse in cold water until water runs clear to remove excess starch, then dry thoroughly with a clean towel.

First fry (blanch)

Heat 2 cups of vegetable oil in a heavy pot to 300°F (if you don't have a thermometer, heat until oil shimmers but does not smoke). Fry the cut fries in batches for 3–4 minutes until just tender and pale. Remove to a paper towel–lined tray and cool. Reserve oil.

Final fry

When ready to serve, heat the reserved oil to 375°F. Fry the blanched fries in batches for 2–3 minutes until golden and crisp. Drain on paper towels, immediately season with kosher salt and black pepper, and toss with 1 tsp vegetable oil to keep them glossy and help sauce adherence.

Portion and season

Divide 1 lb 80/20 ground beef into 4 equal loose balls (~4 oz each). Lightly season the top side of each ball with 1/8 tsp salt and a pinch of black pepper. Keep meat cold until cooking.

Cook and smash

Heat a cast-iron griddle or heavy skillet over medium-high heat and add 1 tbsp neutral oil. Place one or two balls on the hot surface, let sear 20–30 seconds, then use a sturdy spatula to press each ball firmly and flat (about 1/4-inch thick). Season the exposed top with remaining salt and pepper. Cook 1.5–2 minutes until deeply browned on the bottom.

Flip and cheese

Flip each patty, add a generous sprinkle of shredded cheddar, and cook another 30–45 seconds until cheese melts and patty is cooked through. Remove to a plate and keep warm while finishing remaining patties.

In a small saucepan over medium heat, melt 1 tbsp butter. Sprinkle 1 tsp flour and cook, stirring, 30 seconds to make a roux. Gradually whisk in 1/2 cup whole milk until smooth and slightly thickened, about 1–2 minutes. Reduce heat to low and stir in 1 cup shredded cheddar until melted and silky. Season with 1/2 tsp mustard, 1/4 tsp salt, and 1/8 tsp black pepper. Keep warm; if it gets too thick, thin with a splash of milk.

Whisk together 1/4 cup mayonnaise, 2 tbsp ketchup, 1 tsp yellow mustard, 1 tsp pickle brine, 1/4 tsp smoked paprika, 1/4 tsp garlic powder, and 1/8 tsp black pepper in a small bowl. Taste and adjust—add a little more pickle brine for tang or a pinch of sugar if you prefer sweeter.

While patties cook, thinly slice 1/2 cup yellow onion and 1 medium tomato. Have 6 pickle slices and the remaining shredded cheddar ready. If you like softened onions, toss slices in the hot griddle for 30–60 seconds until just translucent.

To assemble the smash burger fries: spread a layer of cheese sauce over a platter of hot fries (or serve cheese sauce on the side). Arrange 2–4 smashed patties over the fries. Drizzle smash sauce over the patties and fries. Scatter sliced tomatoes, pickles, and onions on top and sprinkle remaining shredded cheddar if desired. Garnish with chopped chives or parsley. Serve immediately while fries and patties are hot.