If nothing else (or, if nothing else besides the freshman fifteen), baking has taught me a lot about failure. For every complicated I managed to nail on the first try are at least three flops. And with baking, all of your failures are very physically present, sitting on the counter in front of you, challenging you to take another bite (maybe it'll taste better on the second tasting?), or to toss the whole thing (which always requires explanations to those you live with).
While my mother is a very accomplished cook, her cooking is sometimes something of a theatrical production, with tantrums in the kitchen and half-cooked food thrown out. I think it was food blogging that taught me to take failure less seriously, to shrug it off and laugh over it with my friends (or, you know, with the Internet). Flops in the kitchen are an inevitable, if unenjoyable, part of baking.
For this cake, it was the simple sponge cake base I just couldn't get right. I skimmed over the long, complicated Fraisier Torte recipe in the Pierre Herme cookbook. Mentally, I dismissed the cake portion as a no-brainer (of course I could whip some eggs and fold in flour! I've done it a hundred times), yet somehow ended up with a hard, dense doorstep of a cake.
Genoise sponge cake is made with a handful of pantry staples, yet it took me three tries to really get the technique down. Much more than a successful baking session, kitchen flops fill you with respect for the magic of baking, of carefully transforming simple ingredients into a fancy finished product when it's so easy to have everything go wrong.
The finished product was definitely worth all the effort and dirty dishes. The sponge cake sandwiches a thick layer of strawberries and mousseline cream, a pastry cream enriched with buttercream. Pierre Herme's version enriches the pastry cream with a French buttercream but also lightens it with a meringue. I've simplified his recipe significantly (who wants to make meringue twice with two separate methods in one recipe?). It's still on the longer side, but is definitely manageable and also so delicious.
I love that this cake showcases the fresh strawberries, which are just coming into season (and are some of my favorite fruits to photograph!) The tricky sponge cake and filling enhance the fragrance of the strawberries, which really is the central flavor.
So if you've got a few free hours, give this cake a try. And if it doesn't quite work out, give it another! It'll work out in the end, I promise.
Click here for the printable recipe.
Yields: one 9-inch cake
Heavily adapted from the Pierre Herme Pastries cookbook
Special equipment: 9-inch springform pan
For the Genoise Sponge Cake
⅔ cup all-purpose flour
¼ teaspoon salt
1 tablespoon butter, melted
1 teaspoon vanilla extract
1 teaspoon lemon juice
½ teaspoon lemon zest
½ cup sugar
For the Pastry Cream
1 cup whole milk
⅓ cup sugar
3 egg yolks
1 tablespoon cornstarch
1 tablespoon butter
1 teaspoon vanilla extract
For the Swiss Meringue Buttercream
2 egg whites
½ cup granulated sugar
¼ teaspoon salt
1/2 cup butter, cubed, softened
½ teaspoon vanilla extract
1 pound fresh strawberries
2 tablespoons kirsch (optional, rum can be substituted)
powdered sugar, for sprinkling
Make the sponge cake. Preheat the oven to 325 F. Line the bottom of a 9-inch springform cake pan with a circle of parchment paper. Do not grease the pan; you want the cake to cling to the sides to allow for better rising.
Sift together the flour and salt over a piece of wax paper. Do not skip the sifting--it’s important to ensuring your cake does not have any lumps.
In a medium mixing bowl, mix together the butter and vanilla extract. Let the butter cool to room temperature. In a small bowl, combine the lemon juice and zest.
Combine the eggs and sugar in a large heatproof mixing bowl. Place the bowl over a pot of simmering water (make sure the bottom of the bowl doesn’t touch the water). Gently heat the eggs and sugar, stirring constantly, until the mixture becomes foamy and is very warm, slightly above body temperature.
Whisk the eggs with a hand mixer or stand mixer on high speed for about 10 minutes, or until the mixture has tripled in volume and is very pale. (If you’re using a stand mixer, it may take slightly less time). When you lift up the whisk, you should be able to draw a clear figure 8 with the mixture.
Remove about ½ cup of the egg mixture and fold it into the butter. With the mixer on medium speed, whisk in the lemon juice and zest, and then gradually whisk in the flour, followed by the egg/butter mixture. Work quickly here, before the eggs deflate too much.
Pour the cake batter into the cake pan and bake for 40 to 45 minutes, or until the center of the cake springs back when touched. Cool the cake upside down on a cooling rack for several hours.
Prepare the mousseline cream filling. First, make the pastry cream. Pour the milk in a saucepan and heat until it begins to simmer. Meanwhile, whisk together the egg yolks, sugar, and cornstarch in a heatproof mixing bowl.
Temper the eggs: gradually pour the hot milk into the egg mixture while whisking the eggs constantly. Pour the mixture back into the saucepan, and cook until it begins to boil. Take off the stove and stir in the butter, followed by the vanilla extract. Pour into a bowl, and cover with plastic wrap, pressed directly onto the surface of the pastry cream. Refrigerate for at least 3 to 4 hours.
About 30 minutes before making the swiss meringue buttercream, take the pastry cream out of the refrigerator and let sit at room temperature.
Make the swiss meringue buttercream. Mix together the egg whites, sugar, and salt in a clean, heatproof mixing bowl. Place the bowl over a pot of simmering water (again, don’t let the bottom of the bowl touch the water) and gently heat the egg mixture, whisking constantly, until it reaches 160 F.
Take the bowl off the heat, and beat with a hand mixer or stand mixer on medium speed for 2 minutes, medium-high for 2 minutes, and high for 5-7 minutes, until the eggs form a stiff, glossy meringue. Turn the mixer to medium speed, and gradually add in the butter a few cubes at a time. Beat the frosting at high speed for another 2 -3 minutes. The mixture may look curdled at first after you add the butter, but it will smooth out. Beat in the vanilla extract.
Make the mousseline cream: With the mixer on medium speed, gradually add the pastry cream you made earlier to the swiss meringue buttercream.
Assemble the cake. Cut the sponge cake in half, into two even layers. Peel off the parchment paper circle. Brush the tops of both layers with the kirsch. (If you do not drink, you can omit the kirsch.)
Set aside about 10 small strawberries (about 1 inch in length) for the sides of the cake. Cut these strawberries in half. Roughly dice the remaining strawberries.
Place one of the sponge cake layers in the bottom of the springform pan. Line the strawberry halves along the side of the pan, cut side facing outward. Spread about half of the mousseline cream over the cake, being careful not to dislodge the strawberries. Scatter the diced strawberries over the cream, and spread the remaining cream over them. Top with the other cake layer.
Refrigerate the cake overnight. Remove the cake from the springform pan, and dust with powdered sugar.