Dice the celery into bite-sized pieces and the apple into similarly-sized pieces.

Finely chop the toasted walnuts and red onion.

In a small bowl, whisk together olive oil, apple cider vinegar, lemon juice, honey or maple syrup, and Dijon mustard until emulsified.

In a large mixing bowl, combine celery, apple, walnuts, cranberries, and red onion, and mix gently.

Drizzle dressing over the salad and toss gently to coat all ingredients.

Allow the salad to rest for about 10 minutes before serving.