In a medium saucepan, heat milk and chocolate hazelnut spread over medium heat. Whisk until combined. Stir in cinnamon and rice and bring to a boil. Cover, reduce heat to low and simmer 20 minutes.
In a small bowl combine eggs and 1/2 cup of hot rice mixture. Stir the egg mixture back into the rice mixture. Stir in nuts.
Ladle mixture into eight 1/2-cup oven-proof ramekins. Place ramekins in a large shallow baking pan and add enough hot water to come halfway up the sides of the ramekins. Bake in water bath 20 minutes, or just until centers begin to set. Remove from water bath and cool to room temperature.
Serve topped with whipped cream, grated chocolate and hazelnuts, if desired.