Linzer Cookies

Steps

1. 1
   Mix the flour, ground almonds, icing sugar, cinnamon, salt and lemon zest. Rub in the butter until the mixture looks like fine crumbs, then add the yolks and press together into a dough without kneading.
2. 2
   Divide in two, flatten into discs, wrap and chill for at least 1 hour.
3. 3
   Heat the oven to 170°C (150°C fan) and line two trays with baking paper.
4. 4
   Roll the dough between sheets of baking paper to 3 mm thick and cut out 6 cm fluted rounds. Cut a 2 cm heart or star from the centre of half of them. Re-roll the trimmings once.
5. 5
   Bake for 10–12 minutes, until pale golden at the edges. Cool for 5 minutes on the trays, then on a rack.
6. 6
   Dust the cookies with windows heavily with icing sugar.
7. 7
   Warm the jam until spreadable, spread a teaspoonful over each whole cookie and press a dusted top onto it so the jam fills the window.
8. 8
   Keep in an airtight tin for a day before serving; they last two weeks.