Preheat the oven to 220C/425F/Gas 7.
Gently cook the apple, cinnamon and butter in a pan for a 5-6 minutes, to soften, stirring occasionally.
Butter the bread slices with the unsalted butter and then generously butter a chef's ring. Place on a serving plate and use the bread slices to line the ring. Spoon the apple filling inside and sprinkle with the brown sugar. Bake in the oven for 8-10 minutes, until golden.
For the creme anglaise, gently heat the milk, cream and vanilla seeds in a pan.
Beat the egg yolks and sugar in a bowl until pale and fluffy. Pour the warm milk mixture on to the egg, and whisk until smooth.
Return the mixture to the pan and whisk until thick. The mixture should coat the back of a wooden spoon.
To serve, remove the Apple Charlotte from the oven and place on a serving plate and pour the creme anglaise over the pudding.