Step 1

Whisk together the mayonnaise, lemon juice, mustard, 1 tablespoon salt and pepper to taste in a small bowl.

Step 2

Toss together the chicken, celery, shallot, dill and parsley in a large bowl.

Step 3

Add the dressing to the chicken and mix gently until combined. Refrigerate at least 1 hour and up to overnight to meld flavors. Garnish with chives.

Step 4

Put the parsley, thyme, onion, carrot, celery and chicken breasts in a medium saucepan. Cover with the broth and bring just to a boil. Reduce the heat to very low and cover. Poach the chicken until firm to the touch, about 20 minutes. Remove the pan from the heat, uncover and cool the chicken in the liquid for 30 minutes.

Step 5

Transfer the chicken to a cutting board and reserve the liquid. Bone and skin the chicken and roughly chop the meat into about 1/2-inch pieces. Discard the bones and skin.

Step 6

Strain the broth and store, covered, in the refrigerator for 3 days or freeze for later use. Remove any fat from the surface of the broth before using.