Add the ham bone to the instant pot and pour in the broth. Add in the apple cider vinegar and bay leaves.
Put the lid on, make sure the steam valve is set to "sealing" and set to "pressure cook" on high for 30 minutes. *Keep in mind that it takes about 15-20 minutes to come up to pressure before it starts cooking. Once it's done, use the quick-release valve according to manufacturer instructions.
Open the lid carefully and use tongs to remove the ham bone(s) and bay leaves. Use two forks to pull off any remaining meat from the bone and add it to the rest of the ham going in the soup. Discard the bone and bay leaves.
Add the ham, onions, garlic, sweet potatoes, carrots, and celery to the pot with the broth. Put the lid back on, turn the pressure release valve to "sealing" and set it to high pressure for 10 minutes.
Once it's done, use the quick release function to release the steam. Carefully remove the lid and add in the lemon juice, salt, and remaining herbs/spices.
Allow it to cool slightly then serve.
Notes
*Black Pepper is a stage 1 AIP reintro. If you don't have enough leftover ham for the recipe, you can just round it out with extra veggies or fry up some bacon and add that to the soup. To make the soup without a ham bone, just add the broth to the instant pot, then skip to step 4 in the recipe instructions and go from there. Omit the apple cider vinegar since we're not using the bone. This recipe makes about 12 cups of soup.