Add oil to coat the bottom of the Instant Pot.
Press SAUTE function + 5 minutes.
Add in onion, celery, and carrots, saute for 2-3 minutes.
Select cancel then press MANUAL +15 minutes (+25 if using frozen chicken).
Add chicken breasts and frozen cauliflower florets, chicken broth, salt, pepper, and buffalo sauce.
Close lid and seal valve.
When the timer goes off, carefully release pressure and remove the lid.
Stir in heavy cream/coconut cream.
Serve and top with crumbled blue cheese and extra sliced celery if desired.