Preheat the oven

• Preheat the oven to 190 °C.

Shape the pastry rings

• Cut rings from the puff pastry with a pastry cutter.
• From half of the rings, cut a smaller hole in the center.
• Place the holed rings on top of the whole rings, pressing lightly.

Brush and bake

• Place the rings on a baking tray lined with parchment paper.
• Whisk the egg yolk with the milk and brush the rings with it.
• Bake for about 20 minutes until golden brown.

Cool the pastries

• Remove from the oven and let the pastries cool completely on a cooling rack.

Make the vanilla pudding base

• Heat the milk in a saucepan.
• In a bowl, mix a little milk with the egg yolks, sugar, cornstarch, flour and salt.
• Slowly pour the hot milk into the egg mixture while stirring continuously.

Thicken the cream

• Pour the mixture back into the saucepan and thicken over medium heat, stirring constantly.
• Add the vanilla extract.
• Remove from the heat, stir in the butter, then cover and let cool.

Fill and decorate

• Fill the cooled pastries with the vanilla pudding.
• Top with fresh blueberries and dust with powdered sugar.