1 Preheat oven to 350 degrees. Grease a 9-inch springform pan. Dust with flour; tap out excess.

2 Beat together butter and 1/2 cup sugar at medium speed until light and fluffy. Add egg yolks, 1 at a time, beating well after each addition. Beat in melted chocolate.

3 Using clean beaters, beat together egg whites and salt at high speed until foamy. Gradually add remaining sugar, beating until stiff, but not dry, peaks form.

4 Alternately fold beaten egg whites and flour into chocolate mixture. Spoon batter into prepared pan; smooth top. 5 Bake torte until a toothpick inserted in the center comes out clean, 35 to 40 minutes. Transfer pan to a wire rack to cool for 30 minutes. Loosen torte by running a metal spatula around sides of pan. Remove sides of pan.

6 invert torte onto a wire rack set over a baking sheet. Remove pan bottom. Using a serrated knife, trim top of torte. Cool completely.

7 To prepare topping, in a saucepan, heat preserves and water over low heat until smooth. Brush topping over torte. Chill for 30 minutes.

8 To prepare glaze, in the top of a double boiler set over simmering (not boiling) water, heat together chocolate, butter, and corn syrup until melted and smooth.

9 Remove pan from over water. Cool slightly. Reserve 1/2 cup glaze.

10 Pour remaining glaze over torte. Using a flat metal spatula, spread glaze evenly over top and sides. Using a pastry bag fitted with a fine writing tip and filled with reserved glaze, pipe "Sacher" on top. Let stand until set.