Season chicken breasts with salt and pepper, then grill or cook on a stovetop pan until fully cooked. Let them cool down, and then cut them into small, bite-sized pieces.
In a large mixing bowl, combine the diced chicken, halved grapes, chopped pecans, diced celery, and finely chopped red onion.
In a small mixing bowl, whisk together mayonnaise, honey, Dijon mustard, apple cider vinegar, salt, and pepper until well combined.
Pour the dressing over the salad and gently toss until everything is evenly coated.
Chill the Sonoma Chicken Salad in the refrigerator for at least 1 hour before serving.