Custard yo-yos with roasted rhubarb icing

Lately, I've been the lucky recipient of several batches of homemade biscuits. Just before leaving for holidays I was presented with some of Elizabeth's amazing shortbread. On arrival in Hobart, a jar of assorted Ottolenghi was waiting for me by my bed. Back in Sydney, the postman delivered a batch of biscotti sent at great expense and with much love from afar, and last weekend, my friend from Canberra came to stay bearing cinnamon meringue stars. So I hope the ones I made for Christmas gifts inspired the same warm feelings.

I made a few different sorts (including these and these) but the custard yo-yos with roasted rhubarb icing were the undisputed stars of the show: a creamy pink fruity filling sandwiched by two perfectly pale yellow cookies. The secret ingredient is custard powder, but if you don't have it, cornflour (cornstarch) will do just as well though your biscuits will be a little less yellow. The pastel palette is part of the appeal I think so if you can find custard powder (it should be readily available in any supermarket), it's worth the sub-$2 investment for the child-like delight those nursery colours inspire. I'll definitely be making them again. Next time, all for myself.




Custard yo-yos with roasted rhubarb icing
Adapted from Sweet by Yotam Ottolenghi and Helen Goh

The icing can be made up to two days in advance. The quantity of rhubarb dictated by the recipe is quite small and you can usually only buy it by the bunch but don't be deterred - just freeze what you don't use by chopping the stalks into pieces, laying them out in a single layer on a baking tray and freezing til firm before decanting into ziplock bags for long term storage, ideally in the amounts needed for future batches of icing!


175g flour, plus extra for dusting
65g custard powder
65g icing (confectioner's) sugar
1/8 tsp salt
170g unsalted butter, at room temperature, cubed
1/4 tsp vanilla extract

rhubarb icing
1 small stick of rhubarb, trimmed, washed and cut into 3cm lengths (70g)
65g unsalted butter, at room temperature, cubed
130g icing (confectioner's) sugar
1/2 tsp lemon juice


Preheat oven to 180 deg C. Line a tray with baking paper.

For the rhubarb icing: spread pieces of rhubarb on tray and roast for 30 minutes, or until soft. Remove from oven and cool, then puree in food processor before adding butter. Add icing sugar and lemon juice and continue to process for a few minutes until it thickens. Transfer to a small bowl and let sit in the fridge to firm up.

For the cookies: In the bowl of a food processor fitted with the paddle attachment, cream butter with flour, custard powder, icing sugar and salt on low speed til the mixture resembles breadcrumbs. Increase speed to medium and beat for about 30 seconds until dough forms.

Reduce oven temperature to 170 deg C and line two trays with baking paper.

Roll dough into balls about 3cm round - they should weigh about 15g. Place on lined trays about 4cm apart. Dip the back prongs of a small fork in the extra flour and then press firmly but gently into the back of each ball so that the cookie flattens to about 3.5cm wide.

Bake for about 25 minutes til the cookies are dry on the bottom but haven't coloured too much. Let cool on trays for about 5 minutes then remove to a wire rack to cool completely.

To assemble, spread 15g of icing on the flat side of a cookie and sandwich with the flat side of another. The forked sides should be facing out.

Once assembled, store in an airtight container.