Start by preheating your oven to 350°F (175°C). Lightly grease a 15x10-inch jelly roll pan and line it with parchment paper, leaving some extra hanging over the edges.

In a large mixing bowl, crack in your eggs plus an extra yolk, then add sugar and vanilla extract. Whisk everything together vigorously until the mixture becomes pale, thick, and fluffy. Slowly pour in your neutral oil while gently stirring to keep the batter moist and rich without overshadowing the chocolate flavor.

In a separate bowl, sift the flour, Dutch-processed cocoa, baking powder, baking soda, and salt together. Think of this as the flavor backbone, blending all the dry ingredients for that deep chocolate kick.

Using a spatula, gently fold the dry mixture into the wet ingredients. Be careful not to overwork the batter; you want it just combined to keep the cake soft and light.

Pour the batter evenly into your prepared pan and smooth the top. Bake for about 10 minutes.

As the cake bakes, get a clean piece of parchment paper ready, big enough to hold the cake when you flip it. Once the cake comes out of the oven, quickly flip it out of the pan onto the fresh parchment paper, so it lands face down.

Carefully peel off the parchment paper the cake baked on. While the cake is still warm and flexible, roll it up gently with the fresh parchment paper inside, starting from the short edge. Rolling it this way “trains” the cake to hold its shape and prevents cracking. Let it cool fully while rolled, resting on a wire rack for 1 hour.

While the cake cools, beat together softened cream cheese and butter until smooth and creamy. Add powdered sugar, vanilla, and a pinch of salt, adjusting with a splash of milk or more powdered sugar to reach a spreadable consistency that holds its shape.

After cooling, carefully unroll the cake and evenly distribute the filling, keeping a narrow edge clear. Roll it back up slowly and tightly, wrap it in plastic wrap, and chill for at least 30 minutes. This resting time helps the filling set and makes the roll easier to slice.

Heat the dark chocolate and heavy cream in the microwave in brief intervals, stirring after each to create a smooth ganache. Stir in powdered sugar, then add milk gradually until the ganache becomes pourable but not runny.

Place the chilled roll on a wire rack with a tray underneath. Drizzle ganache on the surface and smooth it gently with a spatula. Then, dig in!