Bring a large pot of salted water to a boil. Add the pasta shells and cook according to the package directions until al dente. Drain well and rinse under cold water until completely cool.

Heat a large skillet over medium-high heat. Add the ground beef, breaking it apart with a spatula. Cook until it is browned, fully cooked, and slightly crispy around the edges. Drain any excess fat and set aside to cool.

In a large serving bowl, whisk together the mayonnaise, sour cream, apple cider vinegar, Dijon mustard, salt, and black pepper until smooth.

Add the cooled pasta shells, crispy ground beef, thawed sweet peas, and grated cheddar cheese to the bowl with the dressing.

Gently toss the mixture until all the ingredients are evenly coated in the dressing.

Cover the bowl and refrigerate for at least 30 minutes before serving to allow the flavors to meld.