In a medium bowl, whisk together the mayonnaise, apple cider vinegar, honey, and Dijon mustard until smooth and well combined. The vinegar will help thin the mayo slightly while the honey adds subtle sweetness and complexity. Whisk for about 30 seconds to ensure the honey is fully incorporated and there are no streaks of mayo remaining.

Sprinkle in the celery seeds, salt, pepper, and onion powder. Whisk until the seasonings are evenly distributed throughout the dressing. I like to taste a small spoonful at this point and adjust the salt or vinegar to your preference—the dressing should be tangy with a balanced sweetness. The result should be creamy, cohesive, and ready to coat your cabbage.