4 cups heavy cream
1 vanilla bean, split lengthwise
Pinch of salt
8 egg yolks
3/4 cup plus 2 tablespoons granulated sugar
½ cup Nutella brand spread
16 teaspoons sugar, for glazing
Preheat oven to 300-degrees. In a medium saucepan, cook the cream with the vanilla bean and salt over moderate heat until the surface begins to shimmer. In a large heatproof bowl, blend the egg yolks and granulated sugar with a wooden spoon. Slowly add the hot cream mixture, stirring gently. Add the Nutella and stir. Strain the custard into a large measuring cup: skim off any bubbles.
Arrange 8 oven safe ramekins in a roasting pan. Slowly pour the custard into the ramekins, filling them all evenly. Set the roasting pan in the center of the oven and carefully pour in enough hot water to reach halfway up the sides of the ramekins. Cover the pan loosely with foil and bake for about 1 hour, or until the custards are firm at the edges, but still a bit wobbly in the center.
Transfer the ramekins to a wire rack to cool completely. Cover and refrigerate until cold, at least 3 hours or up to 7 days.
Preheat the broiler. Sprinkle 2 teaspoons of the sugar over each custard in a thin,even layer. Broil the custards as close to the heat as possible until the sugar is evenly caramelized, 30 seconds to 2 minutes. Let cool slightly and serve at once.