Bring a large pot of salted water to a rolling boil. Add rotini pasta and cook according to package instructions, typically about 8–10 minutes, until al dente. Once cooked, drain the pasta in a colander and immediately rinse it under cold water.

While the pasta is cooking, chop the sharp cheddar cheese, mini dill pickles, and red onion into small, bite-sized pieces.

In a medium-sized mixing bowl, combine mayonnaise, sour cream, dill pickle juice, fresh dill, salt, and pepper. Whisk until creamy and uniform.

In a large mixing bowl, combine the cooled rotini pasta with the chopped cheese, pickles, and red onion. Gently fold the ingredients together.

Pour the dressing over the pasta mixture and toss until well-coated.

Cover and refrigerate the salad for at least 2 hours before serving.