Preheat oven to 150ºC (300ºF). Cook the cream in a saucepan over high heat until it is hot but not boiling. Place the eggs, extra egg yolks, sugar, vanilla and cinnamon in a bowl and whisk until well combined. Gradually add the hot cream, whisking well to combine. Pour into a 7 cup-capacity (1.75 litre) ovenproof dish and sprinkle with nutmeg. Place into a deep baking dish and pour in enough boiling water to come halfway up the sides of the dish. Bake for 1 hour or until the custard is just set. Sprinkle with nutmeg to serve. Serves 6.