You can do more complicated decorations – and get out your piping bag – if you enjoy that kind of thing, but snowy Christmas trees always seem lovely to me. Make sure to get royal icing sugar instead of the regular kind – it gives you a thicker mixture, which coats biscuits more effectively – and add the juice little by little. You can colour the icing if you like – use a dot of food colouring on the tip of a cocktail stick to colour a portion of it. Pale blue looks beautifully frosty, or you can opt for Christmas colours.
Prep time: 45 minutes, plus chilling, cooling and setting time
Cook time: 20 minutes
For the shortbread
50g golden caster sugar
finely grated zest of 1 small orange
125g plain flour, plus extra for dusting
¼ tsp ground allspice
½ tsp orange flower water (optional)
150g royal icing sugar
orange or lemon juice, as needed
sprinkles, silver balls or pearlescent dragees
Cream the butter and caster sugar until light and fluffy.
Beat in the orange zest.
Sift the flour, cornflour and allspice together and add them gradually to the beaten butter (mix on low speed if using a stand mixer).
Add the orange blossom water if you’re using it. Don’t over-mix.
Wrap in cling film and chill for 20-30 minutes.
Heat the oven to 170C/160C fan/gas mark 3½. Line two baking trays with baking paper.
On a lightly floured work surface, roll out the dough to a 5mm thickness and, using a 7cm-tall Christmas-tree cutter, stamp out the shortbread shapes.
Gather the scraps and re-roll them as necessary (the fewer times you do this the better, as it will toughen the dough).
Lay the shortbreads on the baking sheets and chill for 20-30 minutes (they will hold their shape better if you do this).
Bake for 15-20 minutes. The biscuits should be pale gold in colour around the edges. The shortbread might seem a little soft in the middle of each one, but it will firm up as it cools.
Leave to cool then move the shortbread to metal cooling racks set over greaseproof paper, to catch icing drips.
Sift the icing sugar into a bowl and add enough citrus juice – stirring all the time – to make an icing that is thick enough to coat the shortbread.
Spread the icing on to the biscuits with the back of a spoon – or pipe it on if you like.
Sprinkle with whatever decorations you’ve chosen and allow to set.