In a preheated 400 degree oven, roast the parsnips, tossed in olive oil, and seasoned with salt and pepper, until golden brown, about 45 minutes.

In a large saucepan or dutch oven, over medium heat, fry the bacon until crisp. Remove the bacon, and reserve, leaving the additional rendered pork fat in the pan. Add the leeks, garlic, and celery to the pan, and saute until volume has reduced by half, about 5 minutes. Add the roasted parsnips, broth, bay leaf, and thyme, turning the heat up to high. Once a boil has been reached, reduce heat to medium-low, and simmer partially covered for 30 minutes. Once 30 minutes have elapsed, taste, and season with salt and pepper. Turn heat off and puree with an emulsion blender, or in small batches with a regular blender. Soup should be pureed, but not entirely smooth. Return soup to pot, and taste for seasoning.

Serve each bowl of soup with crumbled bacon bits and additional parsnip curls.