After talking with a friend about Japanese~French Pastries, I was inspired to create a dessert using matcha. I’m a visual person, so I couldn’t wait to work with the lovely green hue of matcha powder. I’d also been wanting to try my hand at making an opera cake, so when I found this recipe online it was perfect!
I’m including the recipe and instructions below word-for-word from the website. I’ve added my own photos and some tips I learned as I worked my way through the directions. The only real change I made to the recipe was using white chocolate for the glaze.
Tip from me: Set out your eggs. Eggs should always be room temperature when you’re baking. If you don’t have time to set them out, you can place them in a bowl of warm water until they reach room temperature. And if you don’t have a scale, get one.
Here we go…
Matcha Almond Sponge Cake
Makes 3 1/4-sheetpan sheets
- 160 grams almond flour
- 110 grams sugar
- 40 grams flour
- 15 grams matcha green tea powder
- 4 eggs
- 4 egg whites
- 55 grams sugar
- 30 grams unsalted butter, melted and cooled
In the bowl of an electric mixer combine the first five ingredients. Whip in high speed for about 5 minutes until it becomes thick and the batter forms a ribbon. Transfer this batter to a large bowl and clean the mixer bowl.
In the electric mixer, whip the egg whites until it starts to form a meringue. Slowly sprinkle the 55 grams of sugar. Continue whipping until a stiff meringue forms.
Fold a third of the meringue into the almond batter. Add the rest of the meringue and fold carefully not to deflate it too much. Add the melted and cooled butter and fold until it is well incorporated.
Divide the batter equally into the 3 quarter sheetpans that we have previously lined with parchment paper and sprayed with pan spray. (Tip from me: If you hate pan spray as much as I do, just put a little butter in the pan and the parchment will stay put.)
Bake in a 375 degree oven for about 10-12 minutes until it starts to turn a little brown. We don’t want a brown cake. We want to keep the green color so remove the pans from the oven when the cake is baked and before it starts to change color. Let the cakes cool until we are ready to assemble the opera.
- 60 grams egg whites
- 120 grams sugar
- 180 grams butter, softened
- 25 grams lemon juice
- 1/4 tsp lemon oil or 1/2 tsp lemon extract
Mix the egg whites and the sugar and place them over a double boiler while you whisk them together. The sugar will start to dissolve and the egg whites will start to turn white and fluffy. Continue whisking until the egg whites feel hot to the touch.
Transfer the bowl to the electric mixer and whip in high speed until light and fluffy and the bottom of the bowl doesn’t feel hot anymore. About 3-5 minutes. (Tip from me: This buttercream is one of the most tasty elements of this dessert!)
Start adding the softened butter by the tablespoon. Keep adding more butter as it is incorporated into the meringue. Once all the butter has been added, add the lemon juice and the lemon oil/extract. It might look as if the buttercream has separated. Don’t worry, keep whipping it because it will come together. Reserve until ready to use.
- 170 grams bittersweet chocolate (58% cacao)
- 170 grams heavy cream
Chop the chocolate into a bowl. Boil the cream and pour it over the chocolate. gently whisk the cream and the chocolate until the ganache is formed. Do not over whisk or it might separate depending on the type of chocolate you have used. We want the ganache to be liquid when we assemble the cake so I recommend making this right before or make it ahead of time and remelt it right before we are going to make the cake.
Lemon Simple Syrup
- 100 grams water
- 100 grams sugar
- 2 tsp lemon extract
Boil the sugar and the water until the sugar has dissolved. Remove from heat and add the lemon extract. Set aside.
- 110 grams bittersweet chocolate
- 110 grams *coating chocolate (see below)
- 35 grams vegetable oil
Melt all the ingredients together over a double boiler and keep warm until we are ready to assemble.
Rather Important Tip from me: *Chocolate coating, by the way, is a mixture of your chocolate + shortening. I used 1 cup: 1 tsp. You’ll want this glaze to harden. I followed this recipe exactly but my glaze was still soft upon cooling. To remedy, I heated it slightly in the microwave (6-8 seconds) and added more hard chocolate from the box. It worked to temper my chocolate so the glaze would harden. Success! Test it for hardening on the back of a spoon before you pour it on your cake.
Assemble the Opera Cake
The most important thing when you are building a cake with many components, is to set your self ready for success. That means, get your mise en place ready. Clean your work area of pots and pans and line all your components in front of you so you don’t go crazy and you work clean. Working clean is 75% of the success in your final product. I promise!
So get your sponges ready, the melted chocolate glaze, the melted ganache, the room temperature buttercream, the simple syrup, an offset spatula and a rubber spatula.
Place the first sheet of matcha sponge on your working surface. It will still have parchment paper on the bottom of the cake. Spread a very very thin layer of chocolate glaze on the top of the sponge cake. Spread the chocolate very thinly over the entire surface of the cake with a metal spatula (offset spatulas work best). Let this glaze harden.
When the glaze has hardened (you can even put it in the refrigerator for a few minutes), turn it over onto a sheetpan that is also lined with parchment paper. So at this point, the glazed side of the sponge is down and you are left with the old parchment paper facing you. Remove this paper and discard. (Tip from me: I chose to glaze the bottom of the cake so I would have a more porous surface for the syrup and a smoother surface to glaze. Either way works. The glaze gives you a nice, clean bottom layer that doesn’t stick to plates.)
Soak the cake with the lemon simple syrup with the help of a pastry brush. Then spread a third of the buttercream over the cake with an offset spatula. It is important to have an even layer because when we cut the cake, we want it to look clean and straight.
After the buttercream, pour a third of the ganache over the buttercream and spread it evenly. (Tip from me: Before pouring, divide your ganache into three ramekins to make sure you will have enough for all three layers. Heat slightly so it pours easily, but not so much that it melts your buttercream.)
Place a second sheet of matcha sponge over the ganache making sure that the parchment paper that was on the bottom is now facing up. Remove the paper and brush the top of the cake with the lemon simple syrup. Spread half of the remaining buttercream over the cake, then spread half of the remaining ganache over it. Place the last sheet of sponge on top. Brush with simple syrup, spread the last bit of buttercream on top and finish with the ganache. There will be a total of 3 layers of sponge, 3 of buttercream and 3 of ganache.
(Tip from me: It may look at mess at this point, but don’t worry! We’re going to trim the edges off. One of my pans was about an inch shorter than the other two but, in the end, even that didn’t matter!)
Refrigerate the cake until the ganache sets.
Spread a thin layer of melted chocolate glaze over the top and let the excess run off the sides. Refrigerate it again so the glaze sets. (Tips from me: My glaze was too thick to run off the sides. It didn’t matter. As long as it spreads and then hardens, you’re fine. Also, cutting your edges off before refrigerating will keep your glaze from cracking. If you score lines in the top (just through the glaze) before it hardens, your portions will also cut clean. For both the edges and scoring, use a hot knife. Just run it under the tap then WIPE DRY and cut. Do this each time you make a cut to keep the edges clean.)