Preheat the oven to 400 degrees F.
the butter in a 6-quart stock pot over medium-high heat. Add the onions and celery
. Season with salt and black pepper, stirring, until the vegetables are soft and lightly golden, about 8 minutes.
Add the bay leaf and garlic, stirring for 2 minutes. Add the stock and turnips and bring the mixture to a boil. Reduce the heat to medium and simmer
, uncovered, until the turnips are very soft and the mixture is thick and creamy, about 1 hour.
Remove the soup from the heat. Discard the bay leaf
. With a hand-held blender
, puree until smooth. Slowly add the cream. Stir to blend. Reseason the soup.
In a small saute pan, over medium heat, render
the ham until crispy. Remove and drain
on paper towels. Set aside. Toss the cornbread with olive oil
. Season with salt and pepper. Place on a baking sheet and toast until golden brown, about 6 to 8 minutes. To serve, ladle the soup into individual bowls. Garnish
with the crispy ham and croutons.