In a medium bowl, whisk together chicken broth, mustard, honey, garlic, dried thyme and onion powder, then season with salt and pepper.
Place chicken thighs and mushrooms in your Instant Pot and season with salt and pepper, then pour chicken broth mixture on top and gently stir so everything is coated.
Cover Instant Pot and seal lid, making sure valve is sealed and securely closed. Manually set time to pressure cook for 15 minutes.
Release pressure naturally for 10 minutes, then open steam valve so that it can fully vent.
Uncover Instant Pot and turn on sauté function, then stir in half-and-half and bacon.
In a separate, small bowl, whisk together cornstarch and water until smooth, then mix into chicken, sautéeing until smooth and thickened.
Once desired thickness is reached, serve hot with rice, noodles or mashed potatoes, or on its own.