Gather your sharp knife, cutting board, large mixing bowl, small bowl, and fork to prepare for assembly.
Poach the chicken breasts in boiling salted water for about 12-15 minutes until fully cooked and tender. Let them cool slightly so they're easier to handle.
Use two forks or clean hands to shred the cooled chicken into bite-sized pieces, checking for any excess moisture or uneven chunks.
Finely dice the celery and red onion, then place them in a small bowl. This will add crunch and freshness to your salad.
In the large mixing bowl, whisk together the mayonnaise, lemon juice, salt, and pepper until smooth and bright.
Add the shredded chicken, diced celery, onion, and chopped herbs to the bowl with the dressing. Gently fold everything together until evenly coated, being careful not to break up the vegetables.
Give the mixture a taste and adjust the seasoning with more salt, pepper, or lemon juice for a bright, balanced flavor.
Cover the bowl and refrigerate the salad for at least 30 minutes. This allows the flavors to meld and the textures to set—making it even more delicious.
Once chilled, give the salad a quick toss, then transfer it to a serving dish. Garnish with extra herbs or cracked black pepper for a fresh finishing touch.