Food & Cooking Recipes Dessert & Treats Recipes Citrus Mousse Filling Be the first to rate & review! 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 May 16, 2017 Print Rate It Share Share Tweet Pin Email Photo: Ngoc Minh Ngo Prep Time: 30 mins Total Time: 40 mins Yield: Makes about 5 1/2 cups This lemony mousse fills our Citrus Mousse Cake with Buttercream Frosting. Ingredients 1 ¼ teaspoons unflavored gelatin (from a ¼-ounce package) 1 ¼ cups granulated sugar 1 tablespoon finely grated lime zest (from 2 limes), plus ¼ cup fresh juice 7 large egg yolks, plus 2 whites ½ cup fresh lemon juice ¼ teaspoon kosher salt 10 tablespoons unsalted butter, cut into ½-inch pieces 1 cup heavy cream 3 tablespoons confectioners' sugar Directions Sprinkle gelatin over 2 tablespoons cold water; let stand until soft, about 5 minutes. Meanwhile, in a medium saucepan off heat, whisk together 1 cup granulated sugar, zest, and egg yolks. Whisk in lime and lemon juices and salt. Add butter; place over medium-high heat. Cook, whisking constantly, until butter has melted, mixture is thick enough to coat the back of a spoon, and small bubbles form around edge of pan, about 5 minutes. Stir in gelatin mixture; cook until completely dissolved, about 1 minute more. Pour curd through a fine-mesh sieve into a nonreactive bowl. Press plastic wrap against surface of curd; refrigerate until cold, about 1 hour (or stir over an ice bath until chilled, about 15 minutes). 3. Whisk cream with confectioners' sugar until stiff peaks form. Whisk curd briefly to loosen, then fold in whipped cream. Beat egg whites with whisk attachment until soft peaks form, then gradually beat in remaining 1/4 cup granulated sugar until stiff peaks form. Gently fold into curd mixture. Refrigerate in an airtight container at least 1 hour and up to 2 days. Rate it Print