Cook the pork. Set Instant Pot to SAUTE and add salt pork, bacon, or ham, and onions, cooking until the pork begins to crisp and the onions are softened.

Deglaze the pan. Pour chicken broth into the pot and deglaze the bottle of the pan making sure to get up the browned bits. Press CANCEL To stop the saute function.

Add remaining ingredients. Add the vinegar and the pack in the greens. These greens will shrink a lot as they cook so aim to fill it about 2/3 of the way full.

Cook. Lock the lid in place and turn the valve to SEALING. Set to HIGH PRESSURE for 10 minutes. When the timer goes off do a quick release by turning the valve to VENTING and let all of the pressure out. Remove the lid, stir the contents of the pot to mix everything together and salt and pepper to taste.