Food & Cooking Recipes Dessert & Treats Recipes Cake Recipes Heart-Shaped Flourless Chocolate Cake 4.3 (15) 5 Reviews By Martha Stewart Test Kitchen Martha Stewart Test Kitchen The recipes developed by our test kitchen team have undergone a rigorous process of development and testing, ensuring that every element is optimal, from ingredient amounts to method and cooking time. This process includes triple-testing recipes to ensure they meet our high standards. The many stellar cooks and food editors who have been part of our team include Sarah Carey, Lucinda Scala Quinn, Jennifer Aaronson, Shira Bocar, Anna Kovel, Greg Lofts, Riley Wofford, Lauren Tyrell, and Lindsay Leopold. Editorial Guidelines Updated on February 4, 2022 Print Rate It Share Share Tweet Pin Email Servings: 14 This chocolaty, custardy dessert is just right for Valentine's Day. The much-loved recipe was developed years ago in Martha's catering kitchen by baker Roberta Kins, who once made 38 of them in a single day for a party. Ingredients Unsalted butter, for pan 1 ½ tablespoons instant espresso powder 6 tablespoons hot water 21 ounces semisweet chocolate, coarsely chopped 6 tablespoons dark rum, preferably Meyer's 6 tablespoons dark rum 9 large eggs ¾ cup granulated sugar 1 ½ cups heavy cream 1 tablespoon confectioners' sugar 1 tablespoon pure vanilla extract Sweetened whipped cream, for garnish (optional) Directions Preheat oven to 350 degrees with rack set in lower third of oven. Butter a 10-by-2-inch heart-shaped pan. Line bottom and sides with parchment paper; set aside. In a small bowl, combine the espresso and water. Stir to dissolve. In a heatproof bowl, combine the chocolates, espresso mixture, and rum over a saucepan of simmer water. Stir until smooth. Remove, and set aside. Over the same saucepan of simmering water, combine the eggs and granulated sugar in a large heatproof bowl. Beat, using a handheld electric mixer, until thick, fluffy, and almost tripled in volume. Whip the cream in a chilled bowl until soft peaks form. Add the confectioners' sugar and vanilla. Fold the melted-chocolate mixture into the egg mixture. Gently fold in the whipped cream. Transfer to prepared pan. Place a large roasting pan in the oven, and fill 1 inch with boiling water. Immediately set the heart pan in the roasting pan. Bake until a toothpick inserted in the center comes out clean, about 1 hour. Remove from oven, and let cool in the water bath. When cool, cover, and refrigerate overnight. Just before serving, uncover the pan, and warm slightly in an inch of warm water to loosen from pan. Invert onto a platter. Pipe the sweetened whipped cream onto the chocolate heart with a decorative tip, if desired. Bryan Gardner Rate it Print