Set Instant Pot on sauté setting and add olive oil.
Brown seasoned, frozen chicken thighs in hot oil.
Deglaze pot with white wine, being careful to scrape up all the browned bits on the bottom of the Instant Pot. Turn IP off.
Add chicken broth and sprinkle chicken with Herbs de Provence.
Using manual setting, cook for 8 minutes, making sure vent is closed.
When chicken is done you can allow to release pressure naturally or use the quick release method.
Stir in both types of mustard.
Turn IP to sauté setting and bring to a boil. Allow sauce to reduce and thicken a bit. If it's very thin you can thicken with 1 tablespoon flour or cornstarch stirred into cold water to make a paste.
Stir in heavy cream, heat through and season with a bit of freshly ground black pepper.
Serve chicken with sauce spooned over.