icing sugar or extra maple syrup, to serve (optional)
Slice the banana into a small bowl and mash using a fork. Add the chopped chocolate and mix to combine.
Lay 2 slices of bread on the work surface. Divide the chocolate and banana mixture between them, spreading it almost to the edges. Top each with a second slice of bread and press together to make a sandwich.
In a shallow dish, whisk together the eggs, double cream, maple syrup and vanilla extract. Melt the butter in a large frying pan over a medium heat. Lay one sandwich into the egg mixture to coat one side, then carefully flip it over so that both sides of the sandwich are soaked in the egg. Lower the sandwich into the hot frying pan and cook for about 1 min on each side, until golden brown and the chocolate has started to melt. Repeat with the second sandwich. Cut the sandwiches in half to serve and sprinkle with a little ground cinnamon and either icing sugar or extra maple syrup if you’re feeling super-indulgent.