300 gmGreek-style yoghurt250 gmraspberries (about 2 punnets), plus extra to serveFor brushing:eggwashDanish pastry125 ml (½ cup)milk, at room temperature1large egg, at room temperature350 gm (2 1/3 cups)bread flour25 gmcaster sugar7 gm (about 1 sachet)dried yeast250 gmchilled unsalted butter, cut into 5mm-thick slicesRhubarb compote2 bunchesrhubarb (about 700gm), trimmed, cut into 4cm lengths220 gm (1 cup)caster sugarJuiceof 1 orange1vanilla bean, split, seeds scrapedCrème pâtissière450 mlmilk1vanilla bean, split, seeds scraped220 gm (1 cup)caster sugar5egg yolks30 gmcornflour
Place yoghurt in a muslin-lined sieve placed over a bowl, cover with plastic wrap and refrigerate overnight to drain (discard liquid).
Meanwhile, for Danish pastry, whisk milk, egg and 60ml warm water in a jug to combine, then set aside. Process flour, sugar, yeast and 1½ tsp fine sea salt in a food processor to combine. Add butter and pulse until just combined (there should still be large chunks of butter). Turn onto a work surface, sprinkle with milk mixture, and mix with your hands until a sticky dough forms. Place in a buttered bowl and refrigerate to prove (overnight). Turn out onto a lightly floured surface. Dust with flour and roll to a 1.5cm-thick rectangle, about 20cm x 60cm. Fold short ends in to meet in centre, then fold in half to form a book-fold. Wrap in plastic wrap and refrigerate until just firm (20-30 minutes). Repeat rolling and folding twice more. Wrap in plastic wrap and rest in refrigerator for at least 30 minutes.
For rhubarb compote, preheat oven to 180C. Combine rhubarb, sugar, orange juice and vanilla in a small baking dish, stir to combine, cover with foil, bake until just tender (12-15 minutes) and set aside.
For crème pâtissière, bring milk and vanilla to the simmer over medium heat. Whisk sugar, yolks and cornflour until pale (3-4 minutes), add hot milk mixture and stir to combine. Transfer to a clean saucepan and stir over medium heat until starting to thicken (5-6 minutes), bring to the simmer and whisk until thick and glossy (3-4 minutes). Remove from heat, transfer to a bowl, cover with plastic wrap and refrigerate until chilled. Stir in yoghurt and refrigerate until required.
Increase oven to 190C. Roll out pastry on a lightly floured surface to a 1.5cm-thick rectangle, about 30cm x 40cm, and cut into twelve 10cm squares. Top each square with about a tablespoon of crème pâtissière, three rhubarb stalks and 2 raspberries. Bring two opposite corners of pastry together to meet in the centre, place on oven trays lined with baking paper and brush with eggwash. Repeat with remaining pastries and bake, swapping trays halfway, until golden and puffed (16-20 minutes). Cool to room temperature and serve with extra raspberries, rhubarb and crème pâtissière.