01 - Boil elbow macaroni according to package directions until al dente. Drain thoroughly and rinse under cold running water to stop cooking and prevent sticking. Transfer to a large bowl and allow to cool completely.
02 - In a separate medium bowl, whisk together mayonnaise, sour cream or Greek yogurt, lemon juice, Dijon mustard, garlic powder, salt, and black pepper until smooth and well combined.
03 - Add cooled macaroni, shrimp, diced celery, red bell pepper, red onion, and fresh herbs to the bowl with the prepared dressing.
04 - Gently fold all ingredients together until evenly coated with the creamy dressing, being careful not to break up the shrimp pieces.
05 - Cover the bowl tightly with plastic wrap and refrigerate for at least 1 hour to allow flavors to meld. The salad can be made up to 24 hours in advance.
06 - Remove from refrigerator and stir gently before serving. Taste and adjust salt and pepper seasoning as needed. Serve chilled.