How to Make It
Make salt and pepper fries. Preheat oven to 450ºF with rack in upper ⅓. Place a sheet pan in oven. Halve potatoes, lengthwise; cut into ½- inch wedges. In a large bowl, toss with 1 tablespoon oil, ½ teaspoon salt, and a few grinds pepper. Transfer to preheated baking sheet, roast in oven 20–25 minutes until golden, flipping halfway through. Toss with ½ teaspoon each salt and pepper.
Finely chop half of the pickles (reserve rest for garnish). In a small bowl, stir together mayonnaise, ketchup, and chopped pickles. Season to taste with salt and pepper. Divide ground beef into 2 equal portions (do not form patties).
Heat a griddle or large heavy skillet over high until very hot, about 2 minutes. Lightly brush with oil. Place beef in pan and smash each mound flat with a spatula, forming 5-inch patties. Season well with salt and cook, undisturbed, until outer edges are brown, about 2-3 minutes.
Flip burgers, season with salt, and cook until medium-rare, about 2 minutes more. Transfer burgers to a plate. Pour off fat. Add buns, cut sidedown to griddle or skillet, and toast until lightly browned, 1-2 minutes.
Place burgers on buns and top with a dollop of sauce and reserved pickles. Serve salt and pepper fries alongside, with remaining sauce for dipping. Enjoy!