Put 1 cup of water into bottom of Instant Pot. Put sausages into water or onto trivet. (Mine were frozen and I put right into the water.) Cook on high pressure for 1 minute. Let pressure naturally release for 10 minutes or so.
Remove sausages from the pot, but leave cooking water in the pot for additional flavor.
Add all remaining ingredients to pot. Pressure cook for 5 minutes. Let pressure naturally release for 10 minutes or so.
Meanwhile, slice the sausage. You can either add it to the sauce or serve it on the side. I chose to serve it with some pasta and Parmesan.
Stir and taste; add additional seasoning, if desired.