A genoise is a type of sponge cake which ends up with a more tender, flavourful crumb than many other types of sponge cake owing to melted butter being added to the batter (other sponge cakes don’t use butter.) It’s also less sweet than other sponge cakes. The cake is firm and sturdy, and doesn’t crumble or fall apart easily.This provides a good foundation for creating desserts from, both in terms of taste, and in terms of physical architecture for assembling more elaborate desserts.
It’s used as a base ingredient for assembled desserts such as Baked Alaska, Sachertorte, petit fours, tortes, etc. Its plain taste helps to highlight other ingredients such as fruit, icings, glazes, buttercreams, etc.
When served on its own, it is usually made in a slope-sided tin, and dusted with icing sugar after being turned out of the tin. But on its own it can be dry, so it is often served with a dollop of fruit preserves, or with syrup or liqueur drizzled on it.
Almost all genoise recipes give enough to make two cakes, because it’s most often used as the base for a “composed” cake. This presents the added challenge of making sure you use two tins the same size, and that you put the same amount of batter in each tin.
The batter is made with eggs, sugar, vanilla, cake flour, and melted butter. Classic French proportions are 30 grams of flour and 30 grams of sugar per each egg,
A genoise uses whole eggs, not just egg white. There is no added leavener, chemical or yeast — instead, the cake’s rising is driven by air that is beaten into eggs. The eggs are whipped with sugar until the mixture triples in volume ( you will lose some volume when the flour and butter are added later.)
Before the eggs and sugar are whipped, though, they are usually heated together in a double boiler just until it’s too hot to put your finger in (some say instead, and more precisely, 35 to 38 C / 95 to 100 degrees F.) Note that not all recipes call for this warming before beating. The theory behind heating the eggs in the double-boiler is that heating them causes them to trap more air.
You can blend the eggs and sugar using a mixer — it will take about 10 to 15 minutes on a stand mixer. Or, you can do the beating by hand right in the pot.
In any event, the batter at this point should be about the texture of whipped cream. When it’s cool, the flour is folded in. This part really should be done by hand, not mixer, because you fold the flour in just until the mixture is blended, no more. Next, the melted butter is gently folded in. To be clear, once even a tidge of flour hits the egg and sugar mixture, there is no more beating, because beating at this stage would toughen it. You don’t even stir — you just fold.
The tin for the cake is usually buttered and floured. In addition to this, you can use buttered greaseproof or waxed paper if you wish.
Note that cake flour is used, not all-purpose or a strong flour.
- Some recipes have you leave the egg yolks out, and call for just egg whites, or just baking soda as the leavener, or for both egg white and baking soda. These recipes, however, are just adaptations, not a proper genoise;
- Some recipes go in the other direction and call for added egg yolks;
- Sometimes a very, very small amount of cornstarch is added. Replacing a bit of the flour with cornstarch can give a finer, tighter crumb and keep the cake moister longer;
- Sometimes a pinch of salt is added;
- Some radicals in the kitchen are now preparing a genoise without butter, saying that butter was only needed to help it stay fresher longer (presumably they feel that modern people prefer stale cake.)
Common problems encountered in making a genoise can be that it doesn’t rise, or that it can shrink and pull away from the sides of the pan.
Genoise cake is named after Genoa in the north of Italy. The French attribute its invention to the people there.
It is not the same as Genoa bread, or Genoa cake.