Amazing DIY chocolate truffles

INGREDIENTS

• 300 ml double cream
• 1 knob unsalted butter
• finely grated zest of 1 clementine
• 300 g good-quality dark chocolate (70% cocoa solids), broken into small pieces
• 1 pinch sea salt
• 1 splash brandy
• 1 handful mixed nuts, (Brazil nuts, toasted almonds and hazelnuts)
• 3 tablespoons cocoa powder, to serve
• 1 pack biscotti, to serve
• 1 bottle Vin Santo, to serve