Use dry stale brioche – if not, place cubed slices of brioche in the oven at 100℃ and leave for 20 minutes, turn off and leave for an hour to dry out.
Cut brioche into 1 inch cubes and place in a 10" x 8" baking dish
Whisk eggs and sugar until pale
Whisk in cinnamon and salt and vanilla
Whisk egg mixture with milk
Add mixture to the baking dish of bread cubes and leave for 5 minutes to soak up the custard
Sprinkle with demerara sugar and bake at 180℃ for 45 minutes until puffy and set
Let cool for 10 minutes before serving with a dusting of icing sugar and some maple syrup