Pick over and rinse the lentils. Chop the onion and garlic, and dice up your leftover ham if you’re adding some in (I did here).
Add all ingredients except for the spinach to your slow cooker or Instant Pot.
Stir the lentils into the liquid. It’s fine if the ham bone isn’t completely covered, but do get the lentils under the broth so that they soften and cook through.
Now choose: Instant Pot, or Crock-Pot?
If using an Instant Pot: Pressure cook on high for one hour, then quick release.
If using a Crock-Pot: Slow cook on low for 10 hours.
Instant Pot or Crock-Pot, finish up here:
Once your stew is done pressure- or slow-cooking, remove and discard the bay leaf. Then, pull the ham bone out of the pot, and cut any remaining meat off of the bone. Stir any usable ham back into the pot and discard the bone.
Stir your fresh spinach into the hot stew by the handful until all of it is just wilted, then serve.
Notes
Lentil stew is best scooped up with some crusty bread, naan, or pita bread. I deliberately left a lot of meat on my ham bone because I’d planned ahead of time to make stew with it, but the recipe will still turn out great, even if yours isn’t as meaty as the one pictured.*** Cooking times and equipment listed here reflect the Instant Pot directions; see alternative slow cooker times in recipe above.