Preheat a fan forced oven to 180ºC (200ºC conventional oven).
Use a 24cm round cake tin as a guide and cut one circle then repeat using a 22cm round cake tin.
Pour cream into a small, heavy-based saucepan over medium heat. Bring to just below a boil, then remove from heat and quickly add dark and milk chocolate and stir until chocolate has melted completely. Allow to sit for 5 minutes to cool slightly, then add almond meal, hazelnuts and Ferrero Rocher and season with a pinch of salt. Mix well.
Line a large baking tray with baking paper. Place the 22cm round of pastry on the baking sheet, spoon the Ferrero Rocher filling into the center, leaving a 3cm border around the edges.
Place second 24cm pastry round on top and press down edges to seal. Brush with beaten egg, decorate at your whim.
Bake for 35 minutes or until pastry is golden brown. Allow to sit for 10 minutes before serving with crème fraiche or thick cream.