Turn the Instant Pot on to the saute/brown function.
Add the olive oil. Once hot, add the chicken and cook until browned. It does not need to be cooked all the way through.
Turn the saute/brown function off.
Add the chicken broth, milk, hot sauce, pasta, and cream cheese, in that order. Don't stir.
Place the lid on the pressure cooker and make sure the pressure valve is closed. Cook on HIGH pressure for 5 minutes.
Do a quick release of pressure, which means to immediately turn the pressure valve to open to release the steam. BE CAREFUL doing this and do it slowly. I like to place a kitchen towel over the valve so the steam does not go straight to the ceiling or cabinets.
Stir to combine the ingredients.
Add the cheddar cheese and ranch dressing, stirring well to combine.
Serve topped with blue cheese crumbles and chopped green onion.
Enjoy!