Truffle chawanmushi

Begin by making the dashi. Place the kombu in the water and leave overnight in the fridge to infuse

The next day, gently heat the kombu-infused water (with the kombu still in it) to 60°C, then keep the water at this temperature for 1 hour

While the dashi infuses, make the foam. Peel the potatoes and dice them, ensuring each piece is the same size. Boil the potatoes in unsalted water until soft – around 10-15 minutes – then drain and allow to steam-dry in a colander

After 1 hour, remove the kombu from the water, increase the temperature to 90°C, then add the bonito and remove from the heat. Leave to infuse for 2 minutes, then strain through a fine sieve and set aside to cool

Run the potatoes through a potato ricer twice to ensure they are very well mashed, then pass through a fine sieve

Place the cream, milk and miso into a small saucepan and gently warm through until well combined. Gradually add this mixture to the potatoes until you have a smooth, thick sauce-like consistency (you may not need all the cream mixture). Season to taste with salt and truffle oil, then transfer to an espuma gun and charge with 2 nitrous gas canisters. Keep the espuma gun in a pan of warm water (ideally around 50°C) until ready to serve

Once the dashi has cooled, weigh out 300g of it and combine with the egg, mirin and light soy, stirring well. Season with a pinch of salt, then pass the mixture through a fine sieve into your chosen bowls (or cleaned eggshells, if you have them!)

Briefly run a blowtorch over the top of the egg mixture to remove any bubbles or air pockets, then cover with cling film and steam for 5-10 minutes, or until the mixture has just set

To serve, unwrap the set egg mixture and top with a few slices of truffle. Cover with the potato and truffle foam, then finish with another slice of truffle, stamped out with a small ring cutter