For the dressing: In a small bowl, whisk together mayonnaise, honey, apple cider vinegar, salt and black pepper. Store in an airtight container in the fridge until you are ready to use. This dressing will last in the fridge for up to 1 week.
For the coleslaw: Add sliced cabbage, grated carrot, and chopped onion to a large bowl and toss to combine.
Toss dressing with coleslaw and place in an airtight container in the fridge for at least 1 hour to allow the flavors of the dressing develop into the coleslaw.