• 150 g (5½ oz) sushi rice
• vegetable oil, for deep-frying
• 150 g (5½ oz) butter, at room temperature
• 300 g (10½ oz) sashimi-grade kingfish, sliced

Rinse the rice under cold running water, drain and place in a large saucepan. Cover with 330 ml (11¼ fl oz/1⅓ cups) of water and bring to the boil over high heat. Reduce the heat to low, cover and cook for 12–14 minutes or until the water has been absorbed and the rice is tender. Remove from the heat, strain and allow to cool.

Add 200 g (7 oz) of the cooled rice and 150 ml (5 fl oz) of cold water to a blender. Season and purée the rice until a fine paste consistency is achieved. Line a large baking tray with baking paper and spread the mixture, at a 3 mm (⅛ inch) thickness, across the paper. Dry for at least 48 hours in a warm, dry place. Depending on the weather, this drying process may take longer. When dry, break into bite-size pieces and store in an airtight container.

To make the puffed rice, heat at least 2.5 cm (1 inch) of vegetable oil in a deep-fryer or large, heavy-based saucepan to 180°C (350°F) or until a cube of bread dropped into the oil turns brown in 15 seconds. Flash-fry the rice pieces, individually, until they take on a whitish, translucent appearance. They will expand to around five times their original size. Drain on paper towel and set aside until ready to serve.

To smoke the butter, season it generously and place in a large resealable plastic bag. Using a handheld food smoker with hickory chips, fill the bag with smoke and seal. Set aside for 1 hour then repeat the smoking process. Alternatively, you can smoke the butter in a food smoker. Put the butter in a tray on an upper rack of the smoker. Place a tray of ice on a lower rack as a heat shield and smoke for 2–3 hours. Remove from the smoker. If some separation in the butter has occurred, put the butter in a bowl over ice and whisk until it re-emulsifies. Place the smoked butter in a piping bag and refrigerate until required.