How to Make It
Combine ketchup and horseradish in a small bowl, stirring with a whisk.
Combine Worcestershire, garlic powder, celery salt, pepper, salt, and beef in a bowl; gently blend with your hands. Form mixture into 4 (3 1/2-inch-diameter) patties.
Heat a large cast-iron skillet over medium-high heat. Coat pan with cooking spray. Add burgers to pan; cook 2 to 3 minutes on each side or until desired degree of doneness. Place 1 burger on bottom half of each bun. Top burgers with ketchup mixture, lettuce, and pickle. Top with top halves of buns.