Set your Instant Pot to sauté mode and allow it to preheat, then add the butter. After the butter melts add the diced onion, celery, and carrots and cook for 3-4 minutes until softened. Turn off the heat and add the garlic then cook for another minute.
While the veggies cook cut some of the ham from the ham bone and finely chop, aiming for around a ¼ cup. After the veggies are done cooking, add the ham bone, chopped ham, chicken broth, split peas, bay leaf, thyme, salt, and pepper to the pot and stir.
Cover with the lid and lock it into place, then set your Instant Pot to manual high pressure for 15 minutes. After cooking allow the pressure to release naturally for at least 10 minutes. Then vent any remaining pressure before removing the lid.
Carefully remove the ham bone and bay leaf, and discard. Stir the soup until well combined, then serve.
Notes
Storage Tips
RefrigeratorStore in an airtight container for up to 5 days. Reheat leftovers in a saucepan set over medium heat until warmed through. You may need to stir in a splash of water or broth to loosen up the soup.Freezing InstructionsLet the soup cool, then transfer it to a freezer-safe container and freeze for up to 3 months. When ready to eat, let the soup thaw in the refrigerator then heat in a saucepan over medium heat until warmed through.