Add the chicken thighs to the pot. Add the ranch packet on top of the chicken, followed by the chicken stock. Gently mix the stock until the seasoning has dissolved.
Lock the lid and cook for 10 minutes at high pressure.
Meanwhile, make the sauce: add the mayonnaise to a mixing bowl. Then add all the herbs and spices (chives, parsley, dill, onion powder, garlic powder, salt, and pepper). Mix together and set aside.
Once the cook time is complete, allow the pressure to release naturally for at least 10 minutes. Then quick-release the remaining pressure. Check that the thickest pieces of chicken have reached 165°F.
Transfer the chicken to a shallow bowl so it can cool quickly. A brief freezer shortcut is fine if you want to speed that up, then refrigerate the chicken promptly.
Place the chicken on a cutting board and finely chop. Then return the chicken to the bowl.
Top with the ranch sauce and mix until well combined. Chill in the refrigerator until ready to serve.
Notes
Timing: Allow 10 minutes at pressure and at least 10 minutes natural release, followed by cooling, chopping, and mixing time. This timing is tested with boneless, skinless chicken thighs; I have not tested chicken breasts with the same timing.Storage: Keep the finished chicken salad refrigerated in a covered container and use it within 3 to 4 days. Do not leave it at room temperature for more than 2 hours.Tip: It's not part of this recipe, but I'd use the broth left in the pot to cook some rice or quinoa.