• Put the rosemary sprigs, bay leaves and whipping cream in a small saucepan and place over a low heat to warm for 10 minutes. Turn the heat off and leave the pan to stand for 30 minutes.
• While the cream is infusing, line a deep-sided container or baking tray, 20 x 30cm, with parchment paper and set aside.
• Strain the infused cream, discarding the herbs, and return it to the saucepan. Place the pan over medium heat and bring up to a simmer.
• Melt the chocolate in a large bowl over a saucepan of simmering water. Or use a double boiler.
• When the cream is simmering, remove the pan from the heat, add the salt, and add to the melted chocolate a third time, making sure that the cream is thoroughly incorporated after each addition. Allow to cool slightly.
• Pour the chocolate mixture onto the lined tray and leave to stand at room temperature for 4 hours, then place in the fridge for 5-6 hours or until set.
• Using a small melon baller, scoop balls of the chocolate out of the ganache, or cut into cubes, then roll in cocoa powder (or the crispy chocolate coating below).

Crispy Chocolate Coating (optional)

• This lovely effect is produced by means of sugar crystallization. By adding chocolate to a sugar syrup at the right moment, you can ‘shock’ the sugar into forming crystals, creating a powdery, sandy texture that’s just right for a truffle coating.
• Put 75g cold tap water and the sugar into a saucepan and place the pan over high heat. Bring to the boil and continue to heat until the temperature of the liquid reaches 135°C or until the syrup at the side of the pan begins to colour.
• Remove from the heat and immediately add the chopped chocolate. Whisk to incorporate the chocolate and continue to whisk until the liquid has completely crystallized.
• Pour the chocolate crystals onto a parchment-lined baking tray and allow to cool. They can be kept in an airtight container in the freezer for up to a month.