01 - In a Dutch oven or large pot, melt butter over medium heat. Add onion, celery, and carrots. Sauté for 4–5 minutes until tender.
02 - Stir in garlic and cook for 1 more minute until fragrant.
03 - Add the ham bone and split peas to the pot.
04 - Pour in chicken broth and water. Add bay leaf, salt, pepper, and thyme.
05 - Bring to a boil, then reduce heat to low. Cover and simmer for 50–60 minutes, stirring occasionally, until peas are soft.
06 - Remove the ham bone. Pull off any meat, shred it, and return it to the soup.
07 - Continue cooking uncovered for 20–25 minutes until the soup thickens and peas have broken down.
08 - Discard the bay leaf. Taste and adjust salt as needed. Serve hot.