Chocolate Cream Puffs with Spun Sugar

To make the custard, place the chocolate, vanilla, and rum in a medium bowl. Set aside. In another medium bowl, combine the sugar, flour, and cornstarch. Add the egg yolks and beat with a handheld mixer until the mixture is pale and thick, 1 to 2 minutes. Set aside.

Heat the milk in a small nonreactive saucepan until it forms a skin. Pour the hot milk gradually over the yolk mixture, whisking constantly until all of the milk is added. Return the mixture to the saucepan and cook on medium heat, stirring constantly with a wire whisk, reaching all over the bottom and sides of the pan, until the custard thickens considerably. Continue to cook and whisk for 1½ minutes more. Scrape the custard on top of the chocolate. Stir until the chocolate is melted and completely combined with the custard. Cover the surface of the custard with plastic wrap and refrigerate until needed. Custard may be kept refrigerated for 2 to 3 days.

Position a rack in the lower third of the oven. Preheat the oven to 400°F.

To make puffs, combine the butter, sugar, and salt with the milk and ⅓ cup water in a 1½- to 2-quart heavy-bottomed saucepan. Bring to a boil over medium heat, stirring occasionally, so that the butter is completely melted by the time the mixture boils. Remove the pot from the stove and pour in the flour all at once; stir with a wooden spoon to form a thick paste. Over medium heat, dry the paste slightly by stirring and pushing it all over the sides and bottom of the pot until the pot looks clean but coated with a buttery film. Transfer the hot paste to the bowl of an electric mixer or a bowl in which you can operate a handheld mixer. Mix for 1 minute to cool slightly. Pour about 2 tablespoons of the egg into the paste and mix until incorporated. Gradually, in 3 or 4 additions, add nearly all of the rest of the egg, beating well after each addition until the eggs are absorbed and the paste is smooth, very thick and shiny, and falls slowly from a wooden spoon.

Add the remaining egg judiciously, only if the paste seems too thick.

Fit the pastry bag with the plain tip and fill it with warm paste. Pipe mounds a scant 1½ inches in diameter and ½ to 5/8 inch tall, about 1½ inches apart, on the cookie sheet or sheets. Brush gently with water. Place a pan of hot tap water on the floor of the oven.

Bake, 1 sheet at a time, until the pastries are puffed and golden brown, 18 to 20 minutes. Turn the oven temperature down to 375°F. Remove the pan of water. Stab the sides of each pastry with a sharp knife to release steam. Bake 5 to 10 minutes more. Turn the oven off and leave the pastries inside 5 minutes more. Remove and cool puffs on a rack. Cooled puffs may be stored in an airtight container in the refrigerator up to 3 days or frozen up to 1 month. Recrisp the pastries in a 400°F. oven for a few minutes if necessary.

To fill the puffs, fit a clean pastry bag with a star tip. Fill the bag with the custard. Puncture the bottom of each pastry with the pastry tip and fill it with custard. Set aside.

To make the caramel glaze, have ready a shallow pan filled with ice water. Stir the sugar with ½ cup cold water in a 3- to 4-cup saucepan until the sugar is completely moistened. Do not stir again during the cooking process as this may cause the syrup to crystallize. Cover and bring to a simmer over medium heat. Uncover and wash down the sides of the pan with a wet pastry brush. Cover and cook for 2 minutes to dissolve the sugar completely. Uncover and cook until the syrup looks pale amber when 1 or 2 drops are spooned onto a white saucer. Swirl the pan gently and continue to cook until drops are medium amber. Plunge the bottom of the saucepan in the pan of ice water for a few seconds to stop the cooking. Prop the caramel pan in a tilted position.

Holding a pastry with your fingers or a pair of ice tongs, dip the top about halfway into the caramel (if using your fingers, be very careful) and set it right side up on a cookie sheet lined with wax paper or parchment. Repeat until all of the pastries are dipped. Pastries may be prepared to this point and refrigerated up to several hours. Set caramel aside in the saucepan until needed.

Five to 10 minutes before serving, heap the glazed pastries into a serving bowl or pile them on a platter. Following the instructions, heat the leftover caramel and spin the sugar. Serve as soon as possible.