Remove the skin and cut one of the onions into chunks. Cut the end off of 2 of the carrots, you don't have to peel them. Cut 2 stalks of celery in half. Add these vegetables to the pot with 6 cups of chicken stock and the chicken thighs.
Add in 2 bay leaves, 1½ tsp of fine grind sea salt or kosher salt, ½ tsp black pepper, and ½ tsp of dried thyme leaves OR 1-2 sprigs of fresh thyme. Put the pressure lid on and turn the valve to seal. Select high pressure and set the time for 20 minutes.
While the broth is being made, peel and cut the remaining 2 carrots into about ½" slices. Cut the celery into ½" slices and peel and dice the onion into ¼-½" dice.
When the time is up, allow the pot to natural release for 5 minutes and then manually release the remaining pressure. Carefully remove the chicken and set on a cutting board to cool. Ladle out the cooked vegetables (I discard them, but you could chop them up and add them back in, they will just be very soft) and broth and strain through a fine mesh strainer. Rinse out the pot to remove any residue. I also suggest rinsing the pressure lid and removing the silver cap to make sure nothing is blocking the venting valve. See post for details.
Return the chicken broth to the inner pot. Add in the remaining ½ tsp of dried thyme or another sprig of fresh thyme and the remaining ½ tsp of pepper if desired. Add in the cut vegetables and 3 cups ( about 6 ounces)of medium egg noodles. Put the pressure lid on and turn the valve to seal. Select high pressure for 1 minute. When the time is up, allow the pot to natural release for 7 minutes and then manually release the remaining pressure. If you see any sputtering from the valve, return it to the sealed position and wait 1-2 minutes and then vent the pressure.
Remove the skin from the chicken and pull off the meat in chunks. Add the chicken meat back to the pot and stir. Add salt and pepper if needed and stir in the parsley, if using. Serve & Enjoy!