1. In a food processor or with an electric mixer, beat the butter, 100 grams of icing sugar and the vanilla until light and creamy. Gradually add the sifted flour, beating until blended. Add the ground nuts and cinnamon, beating well.

2. Divide the dough in two, roll into balls, cover with plastic wrap and refrigerate for one hour to firm up.

3. Heat the oven to 180C and line two baking trays with baking paper. Taking two teaspoons (about 30 grams) of dough at a time, roll it into small balls between your palms and place on the trays. Bake for 15 to 17 minutes until lightly golden on top and firmly golden on the base, switching the trays around halfway through.

4. Gently bury the cakes in a bowl of icing sugar for 30 seconds, then turn each cake and bury again for 30 seconds – the heat will help fuse the sugar to the cake. Cool completely, and store in an airtight container.