Turn Instant Pot onto saute and wait for it to get hot. When hot add the butter. Allow to melt then add the chicken, onion, garlic, salt, pepper, poultry seasoning, and thyme. Cook until chicken turns white.
Turn Instant Pot off and add the veggies. Add the noodles by layering them and breaking apart any big clumps. Add chicken broth and close Instant Pot.
Select manual and set timer for 8 minutes. If you have a newer model Instant Pot, you will not have the manual button. Instead select the pressure cook button. When timer is up allow a natural pressure release for 5 minutes. After 5 minutes, release any remaining pressure and turn pot off.
After you open the pot, scoop out 1/2 cup of broth and add it to a small bowl. In the small bowl, mix in corn starch. Stir until smooth.
Turn Instant Pot back onto saute and add the corn starch mixture. Stir and allow it to come to boil. When it comes to a boil turn it off but continue to stir (you don't want anything to stick).
Serve and enjoy!