Sanding nuts
sablage
Sanding nuts means coating roasted nuts, seeds or dried fruit in crystallised sugar. The result is a crisp matte shell that also protects the nut from moisture.
Sugar and water are boiled to roughly 115–118 °C, then taken off the heat and the nuts stirred in. As it is stirred the syrup loses heat and crystallises, wrapping the nuts in a white sandy layer — the stage that gives the technique its name, from the French sable, "sand".
From here the process forks. Stop, and you have nuts in a matte sugar shell. Return the pan to the heat and keep going, and the sugar melts again and caramelises, coating the nuts in a glossy amber glaze — this is how caramelised nuts and the base for praliné are made.
Roast the nuts first and use them warm: cold nuts chill the syrup sharply and the crystallisation comes out uneven.