Stir cabbage and carrots together in a large bowl.
Whisk creamy salad dressing, mayonnaise, buttermilk, sour cream, honey, apple cider vinegar, lemon juice, salt, basil pesto, mustard, cayenne pepper, celery seed, onion powder, ground black pepper, and garlic powder together in a bowl until smooth and creamy.
Pour half the dressing over the cabbage mixture and toss to coat. Gradually add remainder of dressing until coleslaw is your desired consistency. Cover bowl with plastic wrap and refrigerate until flavors combine, at least 3 hours.