Preheat your oven to 350°F (175°C) and generously grease a 9-10 inch ovenproof pan with butter.

In a medium bowl, whisk together eggs, vanilla essence, sugar, heavy cream, and milk until smooth.

Slice stale croissants in half and arrange the bottom halves in the prepared pan.

Sprinkle half of the chocolate chips and raspberries over the croissant bases, then pour half of the custard mixture over this layer.

Place the top halves of the croissants over the existing layers, pour remaining custard mixture over them.

Sprinkle the remaining chocolate chips and raspberries on top before baking.

Cover with foil and bake for 25 minutes, then remove foil and continue baking for 10-15 minutes until set.

Allow to cool for about 5 minutes before serving, dust with confectioner's sugar and add fresh raspberries.