Season chicken with salt and pepper.
Set the Instant Pot to sauté and add oil. Once heated (you will hear a crackle/pop or two), add the onions, carrots, celery, and leeks. Stir and allow to cook 4-5 minutes. Add in the minced garlic and seasonings (minus bay leaf). Stir and cook 1 minute.
Cancel the saute setting.
To deglaze the pot: Pour in the chicken stock and water. Using a wooden spoon, stir and scrap along the bottom of the pot to remove any brown bits that were created from sautéing. This will help to prevent a "burn" notice.
Add the chicken to the pot, water, and bay leaf. Stir well.
Place the lid on, set the vent to the sealed position and the pot to Pressure Cook on HIGH for 7 minutes.
It will take 8-10 minutes to come to pressure. After the timer has gone off, allow for a 10 minute natural release before doing a quick release to remove any remaining pressure that may be remaining in the pot.
Remove the lid and, using tongs, carefully remove the chicken breasts to a cutting board.
Hit cancel on the Instant Pot and select the sauté button.
Allow the soup to come to a boil and add in the egg noodles. Stir and cook 5 minutes, or until the noodles are al dente.
Remove the bay leaf. Add in the lemon juice (optional).
Using two forks, shred the chicken breast. Return the chicken to the pot, add in the frozen peas and stir well. Season with additional salt and pepper, to taste. *SEE NOTES BELOW ON SODIUM
Serve warm, garnished with parsley and your favorite crackers. Enjoy!