01 - Place the sliced apples in a bowl and toss with lemon juice to coat evenly, preventing oxidation and browning.
02 - Heat a dry skillet over medium heat. Add the chopped walnuts and toast for 3–5 minutes, stirring frequently until fragrant and lightly golden. Remove from heat and set aside to cool.
03 - In a small bowl, whisk together the olive oil, apple cider vinegar, Dijon mustard, honey, salt, and black pepper until fully emulsified and smooth.
04 - In a large mixing bowl, add the prepared apples, sliced celery, minced shallot, and cooled toasted walnuts.
05 - Pour the dressing over the salad mixture. Toss gently but thoroughly to ensure all ingredients are evenly coated.
06 - Transfer the salad to a serving platter. Garnish with chopped parsley if desired. Serve immediately for optimal crispness.