Decadent Ding Dong Sheet Cake with Cream Filling Step-by-step instructions

Before you start

Before you begin, ensure your chocolate sponge cake is completely cool to the touch. If the cake is even slightly warm, the cream filling will melt upon contact, compromising the structural integrity and texture of the dessert.

Have all your ingredients measured and ready, and ensure your mixing bowl and whisk attachment are chilled. Clear a dedicated space in your refrigerator, as the cake will require time to set before it is ready to be sliced and served, ensuring the ganache is firm.

Instructions

Whipping the cream

1. 1Prepare the filling
   In a chilled bowl, whip the heavy cream until stiff peaks form. Ensure the cream is cold before starting to achieve the best volume and stability for the filling.
   Look for The cream holds stiff peaks when the beaters are lifted.
   Tip Place the bowl and beaters in the freezer for ten minutes before whipping to speed up the process.

The cream should be light, fluffy, and hold stiff, upright peaks when the whisk is lifted. It should look smooth and feel dense enough to hold its shape when spread between the cake layers. If it looks liquid or thin, continue to whip for another thirty seconds, watching closely to avoid over-mixing into butter.

Layering the sponge

2. 2Assemble the cake
   Slice the chocolate sponge cake horizontally into two even layers. Spread the prepared whipped cream evenly over the bottom layer using an offset spatula. Place the second layer of cake on top, pressing down gently to secure the filling.
   Look for The surface of the cream is smooth and level before placing the top layer.
   Tip Use a long serrated knife to ensure a clean, even cut through the sponge.

The filling should be spread in an even, level layer that reaches the very edges of the bottom sponge. When the top layer is placed, ensure the cake is centered. The assembly should look uniform, with no gaps or overflowing cream at the sides. If the cream pushes out, carefully wipe it away for a clean look.

Glazing with ganache

3. 3Make and apply the ganache
   Heat the remaining heavy cream in a saucepan until it just begins to simmer. Pour the hot cream over the chopped chocolate and let it sit for two minutes. Whisk until smooth and glossy. Pour the ganache over the cake and spread it to the edges with an offset spatula. Ensure the egg-containing sponge reaches 160°F (71°C) if baked fresh.
   Look for The ganache is smooth, shiny, and thick enough to coat the back of a spoon.
   Safe temperature 160°F (71°C) internal temperature (egg dishes)
   Tip Do not overheat the cream, as this can cause the chocolate to seize or separate.

The ganache should be poured slowly starting from the center and spread gently toward the edges. It should have a mirror-like shine and fully cover the top of the cake.

Once spread, the ganache should look smooth, with no visible streaks or clumps. Place the cake in the fridge to allow the ganache to set properly.

Common mistakes

A common mistake is rushing the cooling process; adding ganache to a warm cake or spreading cream on a warm sponge will lead to a messy, unstable dessert. Another error is over-whipping the cream, which can turn it grainy and buttery rather than light and airy.

Finally, ensure the chocolate is chopped into very small, uniform pieces before adding the hot cream; large chunks will not melt evenly, resulting in a lumpy ganache that lacks a smooth, professional-looking finish.

How to tell it’s done

The cake is ready once the ganache has firmed up in the refrigerator, typically requiring at least one hour of chilling. The ganache should feel set to the touch but remain soft enough to slice through without cracking.

The cream filling should be firm and stable, and the sponge should be moist throughout. The eggs in the sponge must reach 160°F (71°C) to be considered fully cooked.

• Egg dishes: 160°F (71°C) in the thickest part