Preheat your oven to 200°C (180°C fan) or 350°F.

Roll out the puff pastry and cut out eight circles using a large cutter. Lightly score a smaller circle within each pastry round to create a border.

Arrange the pastry circles on a baking tray lined with parchment paper or lightly dusted with flour.

Brush each piece with beaten egg white and sprinkle with caster sugar for a golden, glossy finish.

Bake for 10 minutes, or until the pastries are puffed and golden brown. Allow them to cool completely.

In a bowl, whisk the egg yolks and sugar together until the mixture becomes pale and fluffy. Add the cornflour and mix well.

Heat the milk in a saucepan until it’s just below boiling. Slowly add the hot milk to the egg mixture while whisking continuously to ensure it doesn't curdle.

Place the mixture back into the saucepan and cook on low heat, stirring constantly, until it reaches a thick consistency.

Add the vanilla extract and butter, stirring until smooth and glossy. If needed, strain the custard to remove any lumps. Chill the crème patisserie under cling film to prevent skin from forming.

Carefully cut around the scored inner circles of the baked pastry and remove the centers to create shells.

Add a teaspoon of sieved strawberry jam to the bottom of each pastry shell.

Spoon in about three teaspoons of crème patisserie, filling each pastry.

Top with a whole strawberry and spoon over a light glaze made from warmed jam. Garnish with a fanned strawberry or dusting of powdered sugar if desired.