Step 1: Rinse the ham hock under cold water. Pat it dry thoroughly with paper towels.
Step 2: In a large Dutch oven or heavy-bottomed pot, heat 1 tablespoon of olive oil over medium-high heat. Sear the ham hock on all sides until nicely browned. Remove the ham hock and set aside.
Step 3: Add another tablespoon of oil to the pot if needed. Reduce heat to medium and add the diced onion, carrots, and celery. Sauté for 8-10 minutes, stirring occasionally, until the vegetables are softened and the onion is translucent.
Step 4: Stir in the minced garlic and cook for 1 minute until fragrant. Deglaze the pot with white wine or a splash of broth, scraping up any browned bits from the bottom of the pot.
Step 5: Return the seared ham hock to the pot. Add the rinsed lentils, bay leaves, dried thyme, and vegetable or chicken broth. Bring the mixture to a boil, then reduce the heat to low, cover, and simmer for 2 to 2.5 hours, or until the ham hock is fall-off-the-bone tender and the lentils are cooked through. Check periodically and add more broth or water if the soup becomes too thick.
Step 6: Carefully remove the ham hock from the pot. Once cool enough to handle, remove the meat from the bone, discarding the bone, skin, and any excess fat. Shred the tender ham meat using two forks.
Step 7: Return the shredded ham meat to the pot. Stir in the chopped fresh parsley. Taste and adjust seasoning with salt and black pepper, adding salt gradually due to the ham hock's natural saltiness. Stir in the apple cider vinegar if using, for an extra burst of flavor.
Step 8: Ladle the hearty ham hock and lentil soup into bowls. Serve hot with a swirl of olive oil and a sprinkle of fresh parsley, alongside crusty bread if desired.