Wash chicken and cut into chunk size pieces and place into the inner pot of the Instant Pot uncooked.
On top of chicken add diced onion, cubed carrots, cubed sweet potato, garlic, chicken broth, tomato paste, balsamic vinegar, mustard, salt, pepper, and bay leaves.
Stir to mix everything together.
Close the lid of the Instant Pot and place the pressure release knob to sealing. Press "manual" and then press the "-" button until the display reads "6". This is setting the IP to a 6 minute pressure cook on high pressure. The IP will start automatically.
When the 6 minute cook is done, you can allow it to release pressure naturally or you can release pressure manually with the knob (be careful). When the pressure is released, remove the lid and add the kale and stir. put the lid back on with the knob still in venting to allow the kale to cook a bit. It is ready in about 5 minutes.