In a large mixing bowl, combine diced sweet onion, chopped dill pickles, mayonnaise, pickle juice, dried dill, garlic powder, and salt. Stir vigorously until well blended, ensuring the mixture is creamy and smooth.

Once dressing is ready, gently fold in the coleslaw mix until every piece is evenly coated.

Cover the bowl tightly with plastic wrap or transfer to an airtight container. Place in the refrigerator for at least 2 hours.

Before serving, taste and adjust salt as needed, stirring well.