In a medium mixing bowl, whisk together the mayonnaise, ketchup, sugar, paprika, vinegar, and garlic powder until smooth. Stir in the water 1 tablespoon at a time until the desired consistency is reached.
Cover the sauce and refrigerate for at least 1 hour. Stir well before serving.
Store the sauce in the refrigerator in a food storage container with a lid or in jar for up to 5 days.
