I'm thrilled to make my debut this month as a Daring Baker! I'll admit, I was nervous and a little scared to see what the first challenge would be. But all of my worry was for nothing. The challenge was an Opera Cake, which is complicated and seems overwhelming, but as long as you go step by step, it's a piece of cake. hehe.
This month's challenge is hosted by Ivonne, Lis, Fran and Shae. And it truly was a challenge! It really tested me, but I feel like I completed a huge accomplishment.
The Opera Cake Challenge is dedicated to Barbara. She's the woman behind the food blog event called A Taste of Yellow, that supports the LiveSTRONG foundation started by Lance Armstrong. Since LiveStrong Day is in May, it's totally fitting that this challenge be for Barbara.
So now let's get right to the cake, since there's a lot to cover. An Opera Cake consists of five elements: the Joconde, or cake, the syrup, that you brush the cake layers with, the (tricky, for me) buttercream, the ganache/mousse layer, and the glaze. Traditionally, Opera Cakes are flavored with coffee and chocolate, and are dark in color. But since it's Spring and our thoughts are turning to lighter flavors and colors, one of the rules we had to adhere to was that our cakes be light in color. Flavors were up to us (yay!) so I immediately knew I'd do my current favorites, raspberry and lime.
The joconde was flavored simply with vanilla, the buttercream was flavored with raspberry, the mousse was white chocolate and lime, and the glaze--lightly flavored with almond. Here's the recipe, with my changes in blue. Oh, I took as many photos as I could, but I made this almost all in one day, and was most often caught up in what I was doing. Sorry!
Opera Cake
This recipe is based on Opéra Cake recipes in Dorie Greenspan’s Paris Sweets and Tish Boyle and Timothy Moriarty’s Chocolate Passion.
For the joconde
(Note: The joconde can be made up to 1 day in advance and kept wrapped at room temperate)
What you’ll need:
•2 12½ x 15½-inch (31 x 39-cm) jelly-roll pans (Note: If you do not have jelly-roll pans this size, do not fear! You can use different-sized jelly-roll pans like 10 x 15-inches.) (I used 2 11x17 jelly roll pans.)
•a few tablespoons of melted butter (in addition to what’s called for in the ingredients’ list) and a brush (to grease the pans)
•parchment paper
•a whisk and a paddle attachment for a stand mixer or for a handheld mixer
•two mixing bowls (you can make do with one but it’s preferable to have two)
Ingredients:
6 large egg whites, at room temperature
2 tbsp. (30 grams) granulated sugar
2 cups (225 grams) ground blanched almonds (Note: If you do not want to use almond meal, you can use another nut meal like hazelnut. You can buy almond meal in bulk food stores or health food stores, or you can make it at home by grinding almonds in the food processor with a tablespoon or two of the flour that you would use in the cake. The reason you need the flour is to prevent the almonds from turning oily or pasty in the processor. You will need about 2 cups of blanched almonds to create enough almond meal for this cake.)
2 cups icing sugar, sifted
6 large eggs
1 tsp vanilla extract
½ cup (70 grams) all-purpose flour
3 tbsp. (1½ ounces; 45 grams) unsalted butter, melted and cooled
1.Divide the oven into thirds by positioning a rack in the upper third of the oven and the lower third of the oven.
2.Preheat the oven to 425◦F. (220◦C).
3.Line two 12½ x 15½- inch (31 x 39-cm) jelly-roll pans with parchment paper and brush with melted butter.
4.In the bowl of a stand mixer fitted with the whisk attachment (or using a handheld mixer), beat the egg whites until they form soft peaks. Add the granulated sugar and beat until the peaks are stiff and glossy. If you do not have another mixer bowl, gently scrape the meringue into another bowl and set aside.
5.If you only have one bowl, wash it after removing the egg whites or if you have a second bowl, use that one. Attach the paddle attachment to the stand mixer (or using a handheld mixer again) and beat the almonds, icing sugar, eggs and vanilla on medium speed until light and voluminous, about 3 minutes.
6.Add the flour and beat on low speed until the flour is just combined (be very careful not to overmix here!!!).
7.Using a rubber spatula, gently fold the meringue into the almond mixture and then fold in the melted butter. Divide the batter between the pans and spread it evenly to cover the entire surface of each pan.
8.Bake the cake layers until they are lightly browned and just springy to the touch. This could take anywhere from 5 to 9 minutes depending on your oven. Place one jelly-roll pan in the middle of the oven and the second jelly-roll pan in the bottom third of the oven. (Next time, I'd do one layer at a time, since they only have to cook for 9 minutes--the cake on the bottom rack got very dark on the bottom, and I had to carefully cut the dark parts off.)
9.Put the pans on a heatproof counter and run a sharp knife along the edges of the cake to loosen it from the pan. Cover each with a sheet of parchment or wax paper, turn the pans over, and unmold.
10.Carefully peel away the parchment, then turn the parchment over and use it to cover the cakes. Let the cakes cool to room temperature.
For the syrup
(Note: The syrup can be made up to 1 week in advance and kept covered in the refrigerator.)
What you’ll need:
•a small saucepan
Ingredients:
½ cup (125 grams) water
⅓ cup (65 grams) granulated sugar
zest and juice of 1 lime
1.Stir all the syrup ingredients together in the saucepan and bring to a boil.
2.Remove from the heat and let cool to room temperature.
For the buttercream
(Note: The buttercream can be made up to 1 month in advance and packed in an airtight container. If made way in advance, you can freeze the buttercream. Alternatively you can refrigerate it for up to 4 days after making it. To use the buttercream simply bring it to room temperature and then beat it briefly to restore its consistency.)
What you’ll need:
•a small saucepan
•a candy or instant-read thermometer
•a stand mixer or handheld mixer
•a bowl and a whisk attachment
•rubber spatula
Ingredients:
1 cup (100 grams) granulated sugar
¼ cup (60 grams) water
1 1/2 tsp vanilla extract
1 1/2 tsp raspberry extract
1 large egg
1 large egg yolk
1¾ sticks (7 ounces; 200 grams) unsalted butter, at room temperature
3/4 cup raspberries (I used frozen) cooked down for a few minutes and strained through a sieve to remove seeds
1.Combine the sugar, water and vanilla bean seeds or extract in a small saucepan and warm over medium heat just until the sugar dissolves.
2.Continue to cook, without stirring, until the syrup reaches 225◦F (107◦C) [*Note: Original recipe indicates a temperature of 255◦F (124◦C), however, when testing the recipe I found that this was too high so we heated to 225◦F and it worked fine] on a candy or instant-read thermometer. Once it reaches that temperature, remove the syrup from the heat.
3.While the syrup is heating, begin whisking the egg and egg yolk at high speed in the bowl of your mixer using the whisk attachment. Whisk them until they are pale and foamy.
4.When the sugar syrup reaches the correct temperature and you remove it from the heat, reduce the mixer speed to low speed and begin slowly (very slowly) pouring the syrup down the side of the bowl being very careful not to splatter the syrup into the path of the whisk attachment. Some of the syrup will spin onto the sides of the bowl but don’t worry about this and don’t try to stir it into the mixture as it will harden!
5.Raise the speed to medium-high and continue beating until the eggs are thick and satiny and the mixture is cool to the touch (about 5 minutes or so).
6.While the egg mixture is beating, place the softened butter in a bowl and mash it with a spatula until you have a soft creamy mass.
7.With the mixer on medium speed, begin adding in two-tablespoon chunks. When all the butter has been incorporated, raise the mixer speed to high and beat until the buttercream is thick and shiny.
8.At this point add in your flavouring (extracts and raspberry juice) and beat for an additional minute or so.
9.Refrigerate the buttercream, stirring it often, until it’s set enough (firm enough) to spread when topped with a layer of cake (about 20 minutes).
For the white chocolate ganache/mousse
(Note: The mousse can be made ahead and refrigerated until you’re ready to use it.)
What you’ll need:
•a small saucepan
•a mixer or handheld mixer
Ingredients:
7 ounces white chocolate
1 cup plus 3 tbsp. heavy cream (35% cream)
1 tbsp lime juice
zest of 2 limes
1.Melt the white chocolate and the 3 tbsp. of heavy cream in a small saucepan.
2.Stir to ensure that it’s smooth and that the chocolate is melted. Add the tablespoon of liqueur to the chocolate and stir. Set aside to cool completely.
3.In the bowl of a stand mixer, whip the remaining 1 cup of heavy cream until soft peaks form.
4.Gently fold the whipped cream into the cooled chocolate to form a mousse.
5.If it’s too thin, refrigerate it for a bit until it’s spreadable.
6.If you’re not going to use it right away, refrigerate until you’re ready to use.
For the glaze
(Note: It’s best to make the glaze right when you’re ready to finish the cake.)
What you’ll need:
•a small saucepan or double boiler
Ingredients:
14 ounces white chocolate, coarsely chopped
½ cup heavy cream (35% cream)
1/2 tsp almond extract
1.Melt the white chocolate with the heavy cream. Whisk the mixture gently until smooth.
2.Let cool for 10 minutes and then pour over the chilled cake. Using a long metal cake spatula, smooth out into an even layer.
3.Place the cake into the refrigerator for 30 minutes to set.
4. After the glaze it set, carefully trim the edges with a serrated knife to get clean edges. Since you're the chef, eat the trimmings while no one is looking.
Assembling the Opéra Cake
(Note: The finished cake should be served slightly chilled. It can be kept in the refrigerator for up to 1 day).
Line a baking sheet with parchment or wax paper.
Working with one sheet of cake at a time, cut and trim each sheet so that you have two pieces (from each cake so you’ll have four pieces in total): one 10-inch (25-cm) square and one 10 x 5-inch (25 x 12½-cm) rectangle.
I cut my layers wrong and ended up with four layers in a rectangle instead of 3 layers in a square. I always sucked at geometry, hehe.
Place one square of cake on the baking sheet and moisten it gently with the flavoured syrup.
Spread about three-quarters of the buttercream over this layer.
Top with the two rectangular pieces of cake, placing them side by side to form a square. Moisten these pieces with the flavoured syrup.
Spread the remaining buttercream on the cake and then top with the third square of joconde. Use the remaining syrup to wet the joconde and then refrigerate until very firm (at least half an hour).
Prepare the ganache/mousse (if you haven’t already) and then spread it on the top of the last layer of the joconde. Refrigerate for at least two to three hours to give the ganache/mousse the opportunity to firm up.
Make the glaze and after it has cooled, pour/spread it over the top of the chilled cake. Refrigerate the cake again to set the glaze.
Serve the cake slightly chilled. This recipe will yield approximately 20 servings.
Photos of the finished cake:
My thoughts: Even though this seems like it would be a very sweet cake, it wasn't. Not the case with some of the other DB'ers, but everyone's tastes are different. Even my husband, who doesn't like things too sweet, said this was delicious and light, and reminded him of the Italian cream cakes he used to have as a kid. Maybe it's all the lime zest that cut the sweetness, I'm not sure. I'll definitely make this again! My kids have requested it for Christmas, in it's original chocolate form, which will be really fun to try.