1-Prepping and Mixing the Batter: Start things off right by preheating the oven to 350°F (177°C). Grease a 10×15-inch jelly roll pan and line it with parchment paper, then grease the parchment for easy removal. Sift together the cake flour, cocoa powder, baking powder, and salt to ensure a smooth texture. For more chocolate dessert ideas, check out similar treats on the site.

2-Prepping and Mixing the Batter: Next, separate the eggs and beat the whites with about 1/4 cup (50g) of the granulated sugar until medium peaks form, which takes around 4-5 minutes. In another bowl, beat the egg yolks with the remaining 1/2 cup (100g) sugar for 1 minute, then mix in the vegetable oil, buttermilk or milk, vanilla extract, and espresso powder for another 2 minutes. This step builds the base of your light, moist sponge.

3-Baking and Rolling the Cake: Gently fold half of the egg whites into the yolk mixture on low speed for 10 seconds, then add the rest and fold for another 10 seconds. Sift the dry ingredients into the wet mix and fold carefully to avoid over-mixing, keeping the batter airy. Spread it evenly in the pan and bake for 12-14 minutes until the top springs back when touched.

4-Baking and Rolling the Cake: Right after baking, invert the warm cake onto a cocoa-dusted towel or parchment, peel off the original paper, and roll it up starting from the narrow end. Let it cool rolled at room temperature for about 3 hours. This technique, as mentioned in the tips, helps prevent cracking and sets the shape nicely.

5-Adding Filling and Topping: Once cooled, unroll the cake gently and spread the whipped cream filling evenly, leaving a 1/2-inch border. Whip the cold heavy cream with sugar and vanilla to medium peaks, and fold in marshmallow creme if you want extra flavor. For the ganache, heat the heavy cream to a simmer, pour it over the chopped semi-sweet chocolate and optional corn syrup, let it sit for 2-3 minutes, then stir until smooth.

6-Adding Filling and Topping: Pour the ganache over the rolled cake and refrigerate for 30-60 minutes before slicing. The total time is about 3 hours and 40 minutes, with just 1 hour of active prep. Remember, baking time might vary, so a 10×15-inch pan works best for that thin layer. If you’re interested in more creamy desserts, this could be a great next recipe.