Roasted Celeriac soup with Chestnut puree

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I'm channeling winter, or at least true fall with an opulent creamed soup topped with an even richer roasted chestnut garnish.  I am attempting to duplicate a soup I had some months back in a restaurant, and it has been a good attempt.

This soup teams up rich, earthy celeriac (celery root) with sweet parsnips, chicken stock, cream and thyme.  Atop this swims a puree of chestnut, sherry and truffle oil.  The three primary ingredients are all roasted; this brings out the warm, woodsy scents and flavors we associate with a hearty fall soup.  I have left the chestnut puree slightly rough to add another texture to the whole dish.

THE RECIPE
2 Quart yield

Preheat oven to 425 degrees Fahrenheit.

3 small bulbs celery root, trimmed and peeled (you may have better luck slicing the peel with a knife rather than a vegetable peeler)
3 large parsnips, peeled

4 oz. pancetta, thick slices or cubed
1/2 small onion, chopped
1 large shallot, chopped
2 stalks celery, chopped
4 cloves garlic, grated

5 cups chicken or vegetable stock
4 sprigs fresh thyme
4 sprigs flat leaf Italian parsley
1 bay leaf
1/2t black peppercorns, coarsely ground with mortar and pestle
 
Sea salt and white pepper, to taste
Dash lemon juice
approximately 1 cup heavy cream
2T cold butter, cut into small pieces

Freshly grated nutmeg, for garnish

Roast celery root for approximately 30 minutes on a sheet pan (the fragrance is incredible!); add parsnips and roast for another 30 minutes.  Remove from the oven, cool and cut into large pieces.  (To save time, roast chestnuts on a lower rack - procedure below.)

While this is in the oven, render fat from the pancetta over low heat in a 3 quart sauce pan.  Saute onion, shallot, celery for 10 minutes; add garlic and saute for another 5 minutes.

MEANWHILE, in another sauce pan, bring stock, thyme, parsley, bay and pepper to a boil and simmer for 20 minutes.  Strain and add stock to the vegetables.  Add the celeriac, parsnips, salt and pepper and simmer for approximately 30 minutes.  Discard the pancetta; add the lemon juice, taste and adjust seasonings.

Prepare the chestnut puree.


ROASTED CHESTNUT PUREE
1 pound chestnuts, plus 8-10 extra pieces (in case of spoiled nuts)

2-3 T dry sherry
1-2 T  white truffle oil
milk and vegetable oil to thin the mixture


Place the chestnuts flat side down on a cutting board.  Carefully slice an X into the rounded side with a sharp knife.  Roast the chestnuts on a sheet pan approximately 15 minutes, until the nut meats are softened.  Do not overcook them, as the inner shells will become tough.  As the chestnuts cook, the shells will burst open.

 Remove from the oven and place in a dish towel; press and roll slightly.  The shells will crackle and open further.  When they have cooled just enough to handle, carefully peel the outer and inner shells and place the nut meats in a bowl.

Soak the nuts in the sherry while the soup is cooking.  Chop the chestnuts in a food processor (yes, I finally broke down and succumbed to one), adding a touch more sherry, truffle and olive oils and some milk to thin the consistency.  Keep some small chunks in the puree.


Cool the soup slightly.  Puree in a blender, adding butter a few pieces at a time.  Pour into a large mixing bowl and swirl in cream until a smooth texture is achieved.  Serve warm, topped with the chestnut puree and garnish with nutmeg.