In a medium bowl, combine the cooked shrimp with lemon juice, olive oil, ½ teaspoon of granulated garlic, and ⅓ teaspoon of cumin. Mix well to ensure the shrimp are evenly coated, then allow them to marinate for about 10 minutes.

Heat a skillet over medium heat and add the marinated shrimp. Sauté for approximately 5 minutes, stirring occasionally, until the shrimp turn pink and are opaque. Transfer them to a plate and let them cool slightly.

In a separate bowl, whisk together sour cream, mayonnaise, Worcestershire sauce, brown sugar, mustard powder, salt, pepper, remaining granulated garlic, and cumin until smooth.

In a large mixing bowl, combine the cooked macaroni, sautéed shrimp, diced shallot, chopped celery, and parsley. Gently fold the ingredients together, then pour the creamy dressing over the mixture and toss until evenly coated.

Cover the bowl with plastic wrap and refrigerate the Shrimp Pasta Salad for at least 30 minutes before serving.