Fill a large pot with water, add a generous pinch of salt, and bring to a rolling boil. Add rotini and cook according to package directions until al dente (usually 8–10 minutes). Drain and rinse briefly under cold water to stop cooking. Set aside to cool.

Heat a skillet over medium. Add the ground beef and break it up with a spatula. Cook until no pink remains and small browned bits appear, about 6–8 minutes. Season lightly with salt and pepper. Drain any excess fat and let the beef cool slightly.

In a large mixing bowl, combine the cooled pasta, cooked beef, chopped lettuce, diced pickles, and shredded cheddar.

In a small bowl, whisk together the mayonnaise, ketchup, mustard, white vinegar, and a pinch of salt and pepper until smooth. Taste and adjust acidity or seasoning.

Pour the dressing over the pasta mixture and toss gently until everything is evenly coated.

Cover and refrigerate for at least 30 minutes so the flavors meld and the salad chills. Taste before serving and add a little more vinegar if you want extra brightness.