Whisk together the buttermilk, mayo, celery salt, pepper, sugar, vinegar, and lemon juice in a large bowl.
Add the coleslaw mix and toss until well coated. For best results I prefer to refrigerate the coleslaw for a half hour before serving. Sprinkle a little paprika on top and serve.
Notes
As you know, coleslaw is a very versatile side dish. Try it with baked fish sticks or country ribs. You'll be out of buttermilk before you know it.