For the cake: Grease and flour a 9" or 24cm round pan.
In a large bowl, mix all ingredients together, adding the eggs and milk the last.
Note that the batter will be runny.
Pour batter in the prepared pan and tap it a bit to even out the batter.
Bake on preheated oven at 350°F/180°C for 35-40 minutes or until inserted toothpick comes out clean.
Remove from over and let it cool down.
Make sure it is no longer warm when you assemble the cake.
Can be made a day in advance.
Cover in fling wrap and place in fridge.
For the Ganache: ***If using microwave, place 200ml cream in big bowl and heat for 10 seconds on full power, add the semi sweet chocolate and heat for another 10 seconds.
Take out from microwave and stir well.
If chocolate is still lumpy, heat it again for another 10 seconds and stir again afterwards.
Repeat as needed but giving it a good stirring in between and the chocolate should melt slowly without heating too much.
***If not using microwave, place the bowl with cream on top of a small saucepan with boiling water, make sure the bottom of the bowl does not touch the water.
Add chopped chocolates and stir continuously until it melts then remove from heat.
Continue stirring until well blended.
Let the chocolate ganache cool down.
Scoop about half of the ganache into another bowl and add the remaining 75ml of cream and mix until well blended.
Put it in the freezer for 7-10 minutes to make it set faster but do not let it freeze.
Take it out of the freezer and whip until it becomes light and fluffy.
This will be the filling and the other will be used for crumb coating.
Most bakers mistakenly add boiling water directly to cold dairy or eggs, which can scramble the proteins and ruin the emulsion of the batter. Understanding how ingredients interact at different temperatures dictates the success of a delicate, runny batter. Structural integrity relies on precision, particularly when moving between liquid fats and dry powders.
The Impact of Fresh Versus Preserved Elements
Fresh whole milk supplies natural lactic acid and emulsifiers that react cleanly with baking soda, producing consistent carbon dioxide bubbles for a tender crumb. Using reconstituted powdered milk alters the protein ratios and often requires a 1:1 ratio adjustment with added water, though the lack of natural fats changes the moisture retention. Similarly, fresh whole eggs contribute water and lecithin, binding the flour starches effectively. Substituting carton egg products removes the natural fat gradient, resulting in a drier cake that stales faster on the counter.
Controlling Ganache Emulsions and Whipping
Ganache requires precise thermal control to avoid seizing the semi-sweet chocolate, which contains at least 40 percent cacao. When melting chocolate in a microwave, heating in strict 10-second intervals prevents scorching the cocoa solids and separating the cocoa butter. Alternatively, a double boiler setup ensures gentle, indirect heat as long as the bottom of the bowl never touches the simmering water below. Whipping the separated filling requires chilling the mixture for precisely 7 to 10 minutes to reach the proper density without solidifying the fats completely.
Storage and Make-Ahead Protocols
Planning ahead simplifies the assembly process significantly. The baked sponge can be wrapped tightly in plastic wrap and stored in the refrigerator for up to 24 hours before frosting. Allowing the cake layers to cool completely to room temperature prevents the ganache from melting during the crumb coating phase.