If using dried Great Northern beans, rinse and soak them overnight in a large bowl of water.

In a large pot over medium heat, cook the bacon until it becomes crispy, about 8–10 minutes. Remove the bacon and leave the drippings in the pot.

In the same pot, add the chopped onion, carrots, and celery. Sauté for about 5 minutes until tender. Add the minced garlic and sauté for another minute.

Return the crispy bacon to the pot and add the soaked beans, chicken broth, thyme, and salt and pepper. Stir and bring to a boil.

Once boiling, reduce heat to low and let simmer for about 60 minutes, stirring occasionally.

Ladle the soup into bowls and garnish with freshly chopped parsley if desired. Serve immediately.