Ingredients (Serves eight)
32 scrubbed Epicure 1897 and Sharpe's Express potatoes from Carroll's heritage potatoes
Step 1 Roasted potato stock
2.5kg Yukon Gold 1980 waxy potatoes
1.5 litres chicken stock
250g spring onions
Preheat oven to 180°C. Wash potatoes and cook for an hour. Lower oven to 160°C and cook for a further one-and-a-half hours. Turn off oven and let potatoes cool in the oven completely. Remove potatoes and hollow out the jacket potatoes. Turn oven back to 180°C and return the skins until they are brown and crisp. Place potato skins, chicken stock and spring onions in a large vacuum bag and seal. Cook at 85°C for six hours. Pass roasted potato stock through a fine sieve. To cook potatoes, put the 32 heritage potatoes with the roasted potato stock in a large vacuum bag and seal. Cook at 70°C for six to eight hours.
Step 2 Coffee and cocoa soil
40g unrefined caster sugar
135g tigernut flour
50g cocoa powder
8g freshly ground coffee powder
3g sea salt
80g brown butter
Preheat oven to 150°C. Place the dry ingredients together and mix well. Drizzle brown butter a little at a time and keep working the mixture as you drizzle until it resembles bread crumbs and forms soil-like balls that vary in size. Spread evenly on a silpat and bake for 12 to 15 minutes. Let cool.
Step 3 Black Bread "Cinders"
220g fresh Japanese breadcrumbs
4 sprigs thyme
19g Cheesemakers' edible ash
Melt butter until it foams; add sprigs of thyme. Sprinkle Japanese breadcrumbs evenly around frying pan, starting from outside and distributing in a single even layer. Toast until golden brown. Season and drain on fat-absorbent paper. When cool, process with ash until it comes together.
Step 4 Shaved chestnuts
500ml canola vegetable oil
1 Japanese mandolin for slicing chestnuts
Preheat canola oil to 160°C. Slice chestnuts length wise into thin slivers, then deep-fry until golden brown. Season and drain on fat-absorbent paper.
Step 5 Parmesan emulsion
1.5kg grated Parmesan
1.5 litres water
285g rapeseed oil
Bring the water to a boil. Add grated Parmesan gradually to the boiling water whilst whisking continuously. Once all the Parmesan has been whisked in, transfer the mixture to the coldest part of the refrigerator until solids have hardened. Reserve the milky liquid and place solids in an upright container. Add rapeseed oil gradually just like when making a mayonnaise.
To finish Sayur bermi (sayur is malaysian for sour - oxalis or other wild sorrel would work)
Aged cider vinegar
Bake potatoes till golden brown. Drain and glaze with chicken glaze and apple vinegar.
Michael Han, head chef and partner, Fifty Three, Singapore