Season chicken with salt and pepper and place in instant pot.
Add chicken broth, milk, ranch seasoning and stir to combine. Add pasta and stir, burying the noodles in the liquid.
Secure the lid, and set the valve to sealing.
Cook on manual or pressure cook, high pressure, for 4 minutes.
Turn valve to quick release, and open pot.
Stir in cream cheese, cheddar cheese and cooked bacon;
Allow to cool for 5-10 minutes. The sauce will thicken as it cools.