In short: Toast nuts yourself even if you bought them ready-toasted — shop-bought nuts rarely have much aroma left. Use the oven in an even layer rather than a frying pan: they heat evenly and do not scorch underneath.
Why it matters
Nuts appear constantly in pastry work — in sponges, in nut pastes, in praline — and it is the toasting that decides their flavour and aroma. Factory toasting fades during storage, which is why toasting them again at home is worth the fifteen minutes.
Preparing the nuts
Spread them in a single even layer on a tray. A crowded tray steams rather than toasts, and a frying pan browns the underside long before the centre warms through.
Judging when they are done
Go by smell and by the colour of a cut nut: the interior should turn golden. Do not take them to dark brown — nuts carry on colouring from their own heat after they leave the oven.
Removing hazelnut skins
Hazelnut skin is bitter and has to come off. Tip the hot nuts into a tea towel, fold it over and rub: most of the skin comes away on its own. What remains will not spoil the result.
Frequently asked questions
Why toast nuts that are already toasted
Factory toasting fades during storage. Doing it again restores the aroma and the crispness the nut is in the dessert for.
Do I have to skin hazelnuts
Yes, the skin is bitter. Rub the hot nuts in a tea towel and it comes away easily.
How do I know when nuts are toasted
By smell and by the golden colour of a cut nut. Stop before dark brown — they keep colouring off the heat.