Prepare the Cabbage and Carrot: If you don't have pre-shredded coleslaw mix, start by thinly slicing the green cabbage. A mandoline slicer makes this super quick and ensures uniform shreds. Peel and shred the carrot. Place both in a large mixing bowl.
Make the Dressing: In a separate medium bowl, whisk together the mayonnaise, apple cider vinegar, sugar, Dijon mustard, salt, and pepper until smooth and well combined. Taste and adjust seasonings if needed – you might want a touch more sugar for sweetness or vinegar for tang.
Combine and Toss: Pour the dressing over the shredded cabbage and carrot mixture. Toss thoroughly until all the vegetables are evenly coated with the creamy dressing.
Chill (Optional but Recommended): For the best flavor, cover the bowl and refrigerate for at least 30 minutes to allow the flavors to meld. This also helps the cabbage soften slightly.
Serve: Give the coleslaw another quick toss before serving. Enjoy!