2. Sift flour, baking powder and salt onto wax paper.

3. Beat remaining butter until soft in large bowl. Gradually beat in granulated sugar until well combined. Beat in egg yolks, chocolate and vanilla until thoroughly combined.

4. Add flour mixture, alternately with milk, beginning and ending with flour. Beat egg whites until stiff in a small bowl; fold into cake batter. Spoon batter evenly over nut mixture in pan.

5. Bake in moderate oven (350 degrees) 45 minutes, or until cake tester inserted in center comes out clean.

6. Loosen cake from edges with a small knife; cover pan with serving plate; invert; shake gently, then lift off pan. Scoop out any nuts and syrup clinging to pan onto cake with a rubber scraper. Serve with whipped cream.