|Preheat the dutch oven over low heat. Wash and prep the squash, onion, and celery.|
|Add the butter to the dutch oven. Once melted, add the vegetables. Cook on low for about 10 minutes. Stir occasionally.|
|Add the chestnuts and just enough milk to cover all the ingredients. Bring to a boil, then simmer for 20 minutes.|
|Preheat the oven to 180°F. Pan fry the sausage slices with a little butter. Transfer the sausage to a plate and reserve inside the 180°F oven to keep warm. (At such a low temp, the plate will be just fine in the oven.)|
|Slice the chestnuts for garnish into thin slivers. In the same skillet with the sausage drippings, pan fry them until the edges brown. Reserve with the sausage slices in the oven.|
|When simmering is complete, use a hand blender to convert the vegetables into a silky purée. Season with salt and pepper to taste.|
|Transfer to serving bowls and garnish with the fried chestnuts and sausage slices.|
We have found cooked, peeled, and packaged chestnuts at our local Korean market.