Preheat over to 375 degrees F. Line a 17x11x1” sheet pan with a butter parchment paper.
Sift together flour and cocoa powder twice and set aside.
Separate 4 eggs, placing yolks in a large bowl and whites in a medium bowl. Beat yolks with 1/2 cup sugar on medium speed in a stand mixer until thick and pale in color. Add the remaining whole eggs, one at a time, blending well between additions.
In another bowl, beat egg whites with remaining 1/2 cup sugar and corn syrup until slightly thickened and frothy. Add egg whites to yolk mixture and beat to beat.
Add flour-cocoa mixture and fold to blend. Spread out on prepared baking sheet. Bake for 15 minutes or until toothpick inserted into center of cake comes out clean. Let cool completely and then invert cake a peel off parchment. Brush cake with brandy.