Nusskipferl (Austrian walnut crescent cookies)

Method

1. Grind the walnuts finely in a food processor, in short pulses, stopping before they turn to paste; they should look like coarse sand.
2. Whisk the flour, sugar, salt and ground walnuts together. Rub in the cold butter until it looks like coarse crumbs, then work in the egg yolk just until a dough forms. Shape into a disc, wrap, and chill for at least 1 hour.
3. Roll walnut-sized pieces of dough into thin logs, about 6 cm long, tapering slightly at the ends, and curve each into a crescent as you set it on a lined baking sheet, spaced well apart.
4. Bake at 170°C for 13 to 15 minutes, until the base is pale gold and the top is still nearly white. They are very fragile hot, so leave them on the tray for 5 minutes before moving them.
5. Mix the icing sugar and vanilla sugar together. While the crescents are still warm, roll each one gently in the sugar mixture until fully coated.
6. Cool completely on a rack, then store in an airtight tin; a light second dusting of sugar just before serving refreshes them if they have sat a few days.

Method in the Thermomix

Written for a TM5 or TM6, 2.2 litre bowl. This covers grinding the walnuts; the dough, shaping and baking are the same as the hand method.

1. Walnuts into the dry bowl. Grind 8 sec / speed 8, stopping before they turn oily and clump.
2. Continue mixing the dough by hand, folding the ground walnuts through with the flour, sugar and salt as in the hand method; the dough is too stiff for the machine’s blades once the butter is worked in.

Notes

• Roll the crescents in sugar while they are still warm, not after they have cooled. Warm butter in the dough is what makes the coating stick properly; cold crescents shed most of the sugar rather than holding it.
• These are meant to be tender, almost crumbly, not crisp. A dough this rich in butter and ground nuts, with very little flour holding it together, falls apart slightly at the first bite by design.
• Chill the dough properly before shaping. A warm dough is too soft to hold the crescent shape and spreads flat in the oven instead of keeping its curve.
• They keep for 2 weeks in an airtight tin at room temperature, and freeze well unsugared for up to 2 months; sugar them fresh after thawing.

Ingredient substitutions

• Walnuts can be hazelnuts, ground the same way, for a different but equally traditional cookie.
• Vanilla sugar can be replaced entirely with icing sugar plus a few drops of vanilla extract stirred through.
• For a firmer, more snap-forward version, reduce the butter by 20 g and add an extra 20 g of ground nuts, though the classic texture is the soft, crumbly one.
• A dusting of cinnamon in the sugar coating is a regional variation worth trying.