Boil the Pasta: Bring a large pot of salted water to a boil, then add pasta and cook until al dente, about 8-10 minutes. Drain and rinse with cold water.

Prepare the Shrimp: In a small pot, boil water and add fresh shrimp, cooking for 2-3 minutes until pink. Drain and cool. If using pre-cooked, chop into pieces.

Chop the Vegetables: Chop imitation crab, celery, red bell pepper, and red onion into small pieces. Set aside in a large mixing bowl.

Make the Creamy Dressing: Whisk together mayonnaise, sour cream, Dijon mustard, lemon juice, Old Bay seasoning, salt, and pepper until smooth.

Combine the Ingredients: Add the cooled pasta, shrimp, and imitation crab to the vegetables. Drizzle with dressing and toss gently until coated.

Chill Out: Cover and refrigerate for at least 1 hour to allow flavors to meld.

Serve and Garnish: Serve chilled, garnished with parsley and a sprinkle of paprika if desired.