For the custard filling, place the cream and milk into a saucepan over a medium heat and bring to a simmer.
Place the egg yolks and sugar into a bowl and whisk together.
Pour the hot milk and cream onto the eggs, whisking continuously. Return to the pan and cook over a low heat, stirring continuously, until just thickened. Remove from the heat and leave to cool.
For the jalousie pastry, preheat the oven to 200C/390F/Gas 6. Place the puff pastry on a lightly floured work surface and roll out until you have enough pastry for two 30cm x 15cm (12in x 6in pieces).
Cut the pastry to size. Place one of the pieces onto a baking sheet, prick it well all over with a fork and brush with half of the beaten egg. Place in the oven and cook for 10-12 minutes, or until just beginning to turn a golden colour, but not completely cooked through.
Remove from the oven and leave to cool slightly. Turn the oven up to 220C/430F/Gas 8.
Spread the cooled pastry with the cooled custard, leaving a 2cm/¾in rim of pastry free from custard around the edge.
Place the strawberries, pointed side down, into the custard until all of the custard is covered by strawberries.
Cut 15 incisions across the width of the other piece of pastry, leaving a 2cm/¾in rim intact along each edge.
Carefully pick up the pastry and lay it over the layer of strawberries. Gently press the edges down to seal the raw pastry to the part-cooked pastry.
Brush with the remaining beaten egg, sprinkle with the sugar and place in the oven for eight minutes. After eight minutes, reduce the heat to 200C/390F/Gas 6 and cook for a further 10-15 minutes or until the pastry is golden-brown and cooked through.
Remove and leave to cool slightly.
Meanwhile, for strwberries romanoff, place the strawberries into a bowl with the orange zest.
Place the cream, sugar and orange juice into a separate bowl and whisk until soft peaks are formed when the whisk is removed from the orange cream.
Place the chartreuse into a saucepan and heat over a high heat. Carefully ignite the chartreuse and, while still flaming, carefully pour over the strawberries and orange zest.
Spoon the orange cream over the chartreuse-soaked strawberries and stir gently to combine.
Serve immediately, alongside the strawberry jalousie.