Heat a frying pan over a medium heat and lightly toast the croissant halves on both sides. Remove from the pan and set aside to keep warm.
Add the sultanas, orange juice and whisky to the pan and simmer until the liquid is slightly reduced. Sprinkle over the grated chocolate and stir well until melted and combined.
To serve, sandwich the croissant halves together on a plate and pour over the sauce.
