Preheat oven to 150'. Grease baking dish.
In a medium bowl, mix together milk, cream, sugar, eggs.
Place baked pain au chocolat into baking dish and pour custard mix over and allow to rest in fridge for 1-2 hours.
Bake for 40-50 minutes (until custard has just set)
To serve, dust with icing sugar and a dollop of whipped cream