This transition period between the seasons is a little erratic to say the least. One day it’s warm and sunny, the next it’s like the middle of winter. It’s either seafood and salad or steamy soup. The other weekend we ducked out to Danks Street to check out a mixer tap and a gas cooktop, sink and extractor for the kitchen reno and also dropped into Fratelli Fresh for a little look-see. It was bucketing down with rain so anywhere that was dry was favourable. When I saw a box of chestnuts and sweet potato I couldn’t help but feel inspired to whip up a warm soup when returning home.
The idea of this soup was taken from two very different places. It’s loosely based on kuri kinton, a Japanese soup made using mashed sweet potato and preserved chestnuts in syrup, often eaten around Japanese New Year.
I’ve taken a bit of a French angle by using thyme, onion, stock and cream to help balance out the natural sweetness of the potatoes, and that packet of purple sweet potato chips and nori I picked up in Chinatown recently garnished the soup nicely. It’s silky and smooth and a definite heart-warmer.
Preheat the oven to 240°C. Cut an X in the hilum (pale end) of each chestnut and arrange them on a baking tray with the unpeeled garlic cloves. Roast for 20 minutes or until the outer shell of the chestnuts has split and slightly pulled away from the nut. Remove them from the oven, allow to cool for a few minutes and peel the shell off. Use a tea towel to buffer the heat as it can really burn when handling these babies. Squeeze the roasted garlic out of the skin and add to the chestnuts. Set aside.
Heat a medium pot over a medium flame add the butter and allow to melt before adding the chopped onion. Cook until soft. Add the potatoes and increase the heat to medium-high, cooking for about 4 minutes whilst stirring to prevent any burning. Add the chestnuts and garlic, thyme, stock and bring to a simmer. Reduce heat slightly and cover. Simmer for about 20 minutes until the potato and chestnuts are tender.
Remove the thyme and discard.
Using a stick blender, purée the hot mixture, stir in the whisky, cream and cracked pepper and serve garnished with sweet potato chips and thin strips of nori.