Heat oven to 350°. Grease a 15x10x1-inch jelly-roll pan with shortening and line with waxed paper, leaving a 1-inch overhang at each end. Lightly grease waxed paper and dust with flour. Set aside. In a medium bowl, using an electric mixer, beat egg yolks at high speed until thick; gradually add ⅓ cup sugar, beating well. Add almond extract and beat until blended. In a separate bowl, sift together flour, ¼ cup cocoa, and salt; fold into egg yolk mixture. Set aside. In a medium bowl, beat egg whites until foamy; gradually add remaining ⅓ cup sugar and corn syrup, beating until stiff peaks form. Fold about one-fourth of the egg whites into yolk mixture. Gradually fold in remaining whites, then fold in almonds. Spread batter evenly into prepared pan. Bake 10 to 12 minutes, or until cake springs back when lightly touched. Sift dusting cocoa onto a clean kitchen towel. When cake is done, immediately loosen it from sides of pan and turn it out onto prepared towel. Carefully peel off paper. Starting at one end, gently – but with confidence – roll cake and towel together. Let cake cool completely on a wire rack, seam side down. Unroll cake and spread it with half of the Rich Chocolate Frosting recipe, stopping 1 inch from one of the ends. Carefully re-roll cake without towel, beginning with the frosting-covered end. Place cake on a serving plate (or a piece of foil-covered cardboard), seam side down. Spread remaining frosting on top and sides of cake. Chill until firm.
Rich Chocolate Frosting
In a heavy saucepan over medium heat, combine chocolate, cream, and butter, stirring often until chocolate melts. Remove from heat. Add powdered sugar and mix well. Set pan in a shallow bowl of ice. Using an electric mixer, beat chocolate mixture at low speed until frosting holds its shape. If needed, add additional whipping cream for spreading consistency.