Peter Gilmore’s smoky chestnut soup

1.Preheat oven to 180C. Cut a cross into the top of each chestnut 2-3 mm deep with a small sharp knife only scoring the shell to the flesh. This is important so they don’t explode in the oven. Place chestnuts on a wire rack and roast in the oven until cuts open up (15-20 minutes). Remove from oven and place in a heatproof bowl covered with foil and set chestnuts aside to cool and steam slightly (10-15 minutes). Peel the chestnuts outer and inner layers to expose the soft nut. Discard shells and turn oven off to cool.

2.Set chestnuts up on a wire rack on the top shelf of a cold oven or a barbecue, such as a kettle barbecue with closed vents and a lid (see note). Place wood chips into a cast iron frying pan and light the wood chips using a large blow torch, then burn for a couple of minutes before blowing out the flames. Place the smoking wood chips in the oven on a lower shelf below the chestnuts and close the door and smoke until smoky-flavoured (20-25 minutes; check after 10 minutes, relight and blow out flames if smoke has disappeared. Set aside until required.

3.Meanwhile, stir celery, shallots and garlic with half the butter in a large saucepan over medium heat until translucent (3-4 minutes). Add stock and turnip and reserved chestnuts, increase heat to high and boil until chicken stock has reduced by half and vegetables are soft (30-40 minutes). Blend with remaining ingredients in an upright blender, or hand held blender, until smooth, season to taste and strain through a fine sieve if desired for extra smoothness. Soup can be made 2 days ahead and reheated before serving.

4.To serve, bring the soup to a simmer over medium-high heat. Whisk cream to soft peaks and reserve one-quarter to serve, then whisk remaining through the soup. Serve in small cups with a dollop of cream and freshly ground black pepper to taste.