Turn the instant pot on “sauté” setting, wait until it displays “Hot”. Add olive oil and onions, sauté it for 2-3 minutes until onion becomes translucent. Add more oil if needed so that the onion doesn’t stick to the pot.
Next, add carrots and celery, cook for 1 minute. Deglaze the pot by adding in chicken broth (if using Better Than Bouillon Roasted Chicken Base. DO NOT BOIL WATER as per the direction on the jar; use room temperature water. See notes below) and stir until the contents in the pot is well mixed, be sure to scrape any bits stuck to the bottom of the pot.
Add wide egg noodles, thyme, and rosemary. If you are using uncooked chicken breasts, coat it with a pinch of salt and pepper and add it to the pot at this time.
Close the lid and turn the knob to “sealing”. Press “pressure cook” (newer models) or “manual” (older models) and set it on High Pressure for 4 minutes. When it is done cooking, QUICK RELEASE the pressure by turning the knob to “venting”.
If you are using rotisserie chicken, shred it and add it in at this time. If you are using chicken breasts, take it out of the pot, shred it, and mix it back in.
Then, add salt and pepper to taste.