YoYo Biscuits with lime butter icing

Living on my own I try not to have too many treats in the house. I don’t know why I say that really other than buying biscuits and sweets for oneself seems self-indulgent. Much easier to buy if you can reasonably say to yourself, maybe X will enjoy these all the while knowing it’s you that will be sneaking the last Kit Kat into your handbag. But sometimes the urge takes me as it did in Ottolenghi last week and I parted with £5.50 for  packet of cookies.

I know. I’m an idiot. Which is why I stared at the label and thought I really should just make these myself.

One ingredient is intriguing: Custard powder. Yoyo have a lovely melting sandy texture. And the custard powder seems to be key. So for the first time in my life I bought some (no, honestly) and set to make up a recipe using little more than common sense and random eating of cookie dough until it tasted like it might work. Ottolenghi uses a passion fruit icing to stick them together. I had a lime in the fridge so that’s what I used.

I used the Thermomix which made it very short work. A food processor would be just as good. But I do love making my own icing sugar in the Thermomix especially when I remember not to breathe in too quickly when I take off the lid.

This recipe makes about 10 biscuits. 4 for me and a few for the neighbours I think. Total cost about £1.50 so what I’ve cost in calories, I’ve saved in cash.

  • 185g unsalted butter
  • 50g icing sugar (or caster blitzed in the Thermomix for 10 seconds/speed 10)
  • 200g plain flour
  • 50g custard powder

For the icing

  • 30g butter
  • 30g icing sugar
  • Juice and zest of a lime


  1. Set the oven to 160c. Line a large baking sheet with baking parchment.
  2. Cream the butter and sugar for 6 seconds/speed 5
  3. Open and add the flour and custard powder. 6 seconds/speed 5
  4. Wet your hands and roll teaspoons full of the dough and place evenly at least 3cm apart on the baking sheet.
  5. Flatten each ball gently with the tines of a fork. Bake for 18 minutes. Don’t let them brown.
  6. Cool on a wire rack before sticking together with the icing. To make the icing, cream the softened butter with the icing sugar and loosen with the juice of the lime and zest.

Note: these go soft if you ice too far in advance, so ice as required.