• Preheat oven to 350 degrees F

Egg Yolk Mixture:

• In a medium bowl, add together egg yolks, ½ cup of sugar, salt, corn syrup, vanilla, and water. Set this bowl inside a larger bowl filled with warm water and beat on high until pale yellow with ribbons form. Remove from the warm water bath and set aside.

Egg White Meringue:

• In a large bowl, add the egg whites and beat on high until soft peaks form. Start adding the ⅓ cup of sugar in three equal parts, beating each time to incorporate. Beat the egg whites on high until stiff peaks form.

Roll Cake Batter:

• Add ½ of the egg white meringue to the egg yolk mixture and gently fold it in until it's mostly mixed in. The batter should be light and airy. Next, sift the flour, cocoa powder, and baking powder together and add this into the batter in three equal parts, gently folding after each time.
• In a small bowl, microwave the oil until it's warm to the touch. Take out ¼ cup of the combined batter from the previous step and completely mix this into the warm oil. Fold this back into the combined batter. Next, add the entire batter to the remaining egg white meringue and fold it in gently.

Baking & Filling the Roll Cake:

• Pour the batter into a parchment lined pan. Bang the pan twice to remove large air bubbles and bake for 15 - 18 minutes. A toothpick inserted in the center should come out clean when it's done. If it's over baked, the cake will be difficult to roll and may crack.
• Take out the cake, invert the pan onto a clean, slightly damp kitchen cloth, and remove the parchment paper from the bottom. Roll up the cake and hold it in place. You can also roll up the cake with the parchment paper used to bake the cake.
• Once the cake is completely cooled, unroll it and fill it with whipped cream or the cream cheese filling and roll it back up. Next glaze the roll cake with the ganache and serve.

Filling (Choose One):

• Whipped Cream filling: Add the cream, sugar, and vanilla to a medium size bowl and beat on medium high speed until you get stiff peaks, about 2 minutes.
• Cream Cheese filling: Beat the cream cheese and butter together in a medium bowl until it's well combined. Add the powdered sugar, milk, and vanilla to the bowl and continue beating until it's smooth and creamy. Add more milk if it's too thick to spread.

Glaze with Ganache:

• Break up the chocolate bar into small pieces and add it into a microwave safe bowl along with the heavy cream. Microwave this in 20 second intervals until the chocolate starts to melt and the cream has warmed up. Stir this together until you get a smooth ganache.
• Place a wire rack on top of a baking sheet and lay the roll cake on top of the wire rack. Slowly drizzle the ganache on top of the cake so that it's entirely covered. Allow the ganache to set and serve.