Pistachio Custard Croissant

_A laminated butter croissant split and filled with silky pistachio crème pâtissière, finished with a brush of syrup, chopped pistachios and a dusting of icing sugar. An ambitious weekend bake that rewards patient lamination._

Ingredients

• 500 g strong white bread flour
• 55 g caster sugar
• 10 g fine salt
• 10 g fast-action dried yeast
• 270 ml whole milk, cold
• 250 g unsalted butter, for laminating (block)
• 1 egg, beaten, for glazing
• 400 ml whole milk, for the custard
• 4 egg yolks
• 80 g caster sugar, for the custard
• 35 g cornflour
• 60 g pistachio paste (unsweetened)
• 25 g unsalted butter, for the custard
• 50 g shelled pistachios, finely chopped
• icing sugar, to dust

Method

Make the détrempe: combine flour, sugar, salt and yeast in a bowl, keeping the salt and yeast apart. Add the cold milk and mix to a shaggy dough, then knead briefly until it just comes together. Shape into a rough rectangle, wrap and chill for 1 hour, then refrigerate overnight to relax the gluten.

Prepare the butter block: place the 250g butter between two sheets of baking paper and bash and roll into a neat 18cm square slab, about 1cm thick. Chill until firm but still pliable.

Lock in the butter: roll the chilled dough into a rectangle roughly 18 x 36cm. Sit the butter slab on one half, fold the bare dough over it and seal the edges. The butter and dough should be the same cool, pliable temperature.

First fold: roll the parcel into a long rectangle about 20 x 60cm, keeping the edges square. Fold in thirds like a letter, wrap and chill for 30 to 45 minutes. Repeat for a second and third fold, chilling between each. Rest in the fridge for at least 1 hour after the final fold.

Make the pistachio crème pâtissière: heat the 400ml milk until steaming. Whisk the yolks, 80g sugar and cornflour to a smooth paste. Pour the hot milk over the yolks, whisking, then return to the pan and cook over a medium heat, stirring constantly, until thick and boiling for 1 minute. Off the heat, beat in the pistachio paste and 25g butter. Cover with cling film touching the surface and chill until cold.

Shape: roll the laminated dough to a 20 x 60cm rectangle, 4mm thick. Trim the edges, then cut into long triangles with a 10cm base. Notch the centre of each base, gently stretch and roll up from base to tip, finishing with the tip tucked underneath.

Proof: space the croissants on lined trays, curving the ends inward. Brush lightly with beaten egg and prove at warm room temperature (around 24 to 26C) for 2 to 3 hours, until visibly puffy and jiggly when the tray is nudged.

Bake: heat the oven to 200C fan. Glaze again with egg and bake for 16 to 20 minutes until deeply golden and crisp. Cool completely on a wire rack.

Fill: beat the cold pistachio custard smooth and transfer to a piping bag. Split each cooled croissant lengthways without cutting all the way through, and pipe a generous line of custard inside.

Finish: brush the cut faces lightly with a little simple syrup if you like extra sheen, then press chopped pistachios onto the exposed custard and dust the tops with icing sugar. Best eaten the day they are filled.