300 gm (2 cups) plain flour
230 gm softened butter
25 gm caster sugar
1 tsp ground cinnamon
For dusting: pure icing sugar and ground cinnamon
6 egg yolks
130 gm caster sugar
35 gm (¼ cup) cornflour
300 ml each pouring cream and milk
3 tsp vanilla bean paste
Combine flour, ¼ tsp salt and 200ml water in an electric mixer fitted with a dough hook and knead until dough pulls away from the sides of the bowl (1–2 minutes).
Turn out onto a lightly floured surface and pat into a 15cm square, wrap in plastic wrap and refrigerate to rest (30 minutes).
Roll out on a lightly floured surface to a 45cm square and trim edges if necessary.
Spread the left two-thirds of the pastry with a third of the butter, leaving a 2cm border.
Fold the unbuttered third of dough over, then fold the left side over to cover.
Pat out any air bubbles, pinch edges to seal, then turn pastry 90 degrees so the folded edge is nearest you.
Repeat the rolling, buttering, folding and turning process once more, then roll out pastry to a 45cm x 55cm rectangle and spread with remaining butter leaving a 2cm border.
Combine sugar and cinnamon in a bowl, sprinkle mixture over butter, then roll into a tight cylinder from the shortest side.
Trim ends, cut in half and wrap each piece in plastic wrap.
Refrigerate one half overnight and freeze the other half for use later (defrost in the refrigerator before using).
For custard, whisk yolks, sugar, cornflour and a pinch of salt in a bowl to combine, then whisk in cream, milk and vanilla.
Transfer to a saucepan and bring to a simmer over medium-high heat, whisking continuously until thick and smooth (4–5 minutes).
Transfer to a piping bag fitted with a 1cm plain nozzle, twist bag to seal and set aside until cooled (1–2 hours).
Preheat oven to 250C.
Cut refrigerated pastry cylinder into 24 even pieces, roll out on a lightly floured surface to 9cm-diameter rounds and line two 12 x 65ml muffin tins, allowing edges to overhang slightly.
Fill with custard to 1cm below rims and bake, turning trays partway through cooking, until golden brown and set (10–12 minutes).
Cool briefly and serve warm or at room temperature dusted with icing sugar and cinnamon.