Prep the shrimp. If using large cooked shrimp, chop them into small, bite-size pieces. Pat them dry with a paper towel so they don’t water down the dip.
Whip the base. In a mixing bowl, beat the softened cream cheese until smooth and fluffy.
Add the mayonnaise and beat until fully combined and creamy.
Layer in the flavor. Stir in lemon juice, horseradish, hot sauce, Worcestershire, Old Bay, garlic powder, and smoked paprika. Taste and adjust salt and pepper as needed.
Add the mix-ins. Fold in the chopped shrimp, celery, green onions, and parsley until evenly distributed. Avoid overmixing; you want small pockets of shrimp for texture.
Chill or bake. For a cold dip, cover and chill for at least 1 hour to let flavors meld.
For a warm version, spread into a small baking dish, top with shredded cheese if using, and bake at 350°F (175°C) for 15–18 minutes until hot and bubbly.
Serve smart. Transfer to a serving bowl, garnish with extra parsley or a light sprinkle of Old Bay, and set out with sturdy dippers like butter crackers, sliced baguette, or bell pepper strips.