Wednesday, May 28, 2008

Tr'opera: Tropical Opera Cake

Our Daring Bakers Challenge #2

From the reference above, it seems that we have now proceeded to our second challenge of Daring Bakers. We are too happy for words and greatly satisfied with our 2nd challenge. The very 1st challenge that we have participated were Cheesecake Pops, and as of this month's challenge, it was our most fearful cake of all time, the Opera Cake. An Opera Cake, consisting of the main jaconde sponge, intensified flavorful syrup, buttercream, mousse, ganache and also glaze, with the usual rectangular shape as part of its identifiable features. We have always been keen to make perfect buttercream with only butter itself, and not buttercream which need to be folded with stiff egg whites. Speaking of the grand Opera cake, which involves jaconde, our unskilled physiques on whipping up a fluffy jaconde wasn't that good either. The last time we tried our hands on jaconde sheets, we ended up feasting on hard tuiles. Over baked, that might be the answer. Wait a minute, it might as well be over whipped egg whites since the batter had sunk quarterly after a few rounds of fold-cum-mix sessions with the rubber spatula. To bake or not to bake, that will be the question this time round.

The 2nd challenge was hosted by Lis and Ivonne, together with the other two newer members of DB; Fran and Shea. Baking an Opera Cake (which is originally made with chocolate, almond and coffee, with coffee buttercream) is kind of challenging, but baking an Opera Cake with light flavors and light colors (white chocolate, vanilla, lemon etc) is way upon challenging - which made this DB Challenge truly a challenge. On the same week itself, which is most probably the first week of the month of May, we sat and brainstormed the availability of flavors to be used to re-create the new Opera Cake quietly, right in front of our computer desk. Matching and pairing up the flavors was neither easy, the unsuitability of two distinctive and individual flavors might lead to bad repercussions; which spells opera cake disaster. We gathered resources and feedbacks from the kids. One suggested that the question should be served to Mom. And why Mom, we wondered for a while. Mother's Day's on the 12th of May, we were too old to be blamed - forgetfulness. That's it! Mom will then decides the flavor of this Opera Cake, specially created for her, with flavors quoted by herself.

Mom hinted that she would love to have a Mother's Day Cake which consists of real chunky hazelnuts to bite on, uber green kiwis to chowed on, white chocolate mousse to licked on and a refreshing cake which will take in passion fruit puree as well. That sounds interesting, think of bright colored fruits, well - think tropical! Thoughts of a soul which undoubtedly belongs to a novice baker whispered softly; that is a very daring move when it comes to a whole new creation of an opera cake. Daring, and our minds are mentally challenged.

The original opera cake recipe was based on Dorie Greenspan's Paris Sweets and Tish Boyle and Timothy Moriarty's Chocolate Passion. Alterations were made, starting off with the jaconde itself. The original jaconde calls for almond meal, but we go otherwise - hazelnut meal, since Mom does not favor almonds. We have
made our very own hazelnut meal to substitute the almond meal.

Hazelnut meal in our local bakery store (Malaysia) was known as grounded hazelnuts and it is blended not as fine as what most hazelnut meal was.

For homemade hazelnut meal; blend a pack of hazelnuts by an electric blender while gradually adding teaspoonfuls of flour to avoid oily paste, and last but not least, sieved the finely blended hazelnuts by spoon-pressure through a flour sifter.
Voila, hazelnut meal! Next up, the buttercream were infused with kiwi puree and passion fruit puree. On the other hand, the syrup was made out of honey with a hint of Australian wine.

As we were afraid that the tropical opera cake might taste too bland, the search for another tropical fruit as the cake's fillings were held. Ripened Alphonso mangoes goes in perfectly! We omitted the white chocolate mousse as there were excess of buttercream left in the refrigerator. The glaze was made out of white chocolate, and the temptation to brush on a thin layer of light green colored apricot glaze were done as well. As to finalize the Tropical Opera Cake as a product, slices of kiwis and halved mangoes were arranged on the surface of the cake. The recipe below will bring about 6 parts; hazelnut jaconde, honey syrup, kiwi and passionfruit buttercream, white chocolate glaze, mango cubes, and the way the cake being assembled.

Part One: Hazelnut
(Note: The joconde can be made up to 1 day in advance and kept wrapped at room temperature)

6 large egg whites, at room temperature
2 tbsp. (30 grams) granulated sugar
2 cups (225 grams) ground blanched hazelnuts
2 cups icing sugar, sifted
6 large eggs

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 hazelnuts, icing sugar and eggs 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 over mix batter)

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.
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 unmould.

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.

Part Two: Honey Syrup

(Note: The syrup can be made up to 1 week in advance and kept covered in the refrigerator.)

½ cup (125 grams) water

⅓ cup (65 grams) granulated sugar
2 tablespoons honey
2 tablespoons Australian wine

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.

Part Three: Kiwi & Passionfruit 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.)

1 cup (100 grams) granulated sugar

¼ cup (60 grams) water

1 tablespoon pure vanilla extract
1 large egg
1 large egg yolk

1¾ sticks (7 ounces; 200 grams) unsalted butter, softened

2 kiwis, pureed and strained through sift (juice wanted)
2 passionfruit, medium-sized, pureed ( juice wanted)

1. Combine the sugar, water and vanilla 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) 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 kiwi juice and passionfruit puree. 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).

Part Four: White Chocolate Glaze
(Note: It’s best to make the glaze right when you’re ready to finish assembling the cake.)

14 ounces white chocolate, coarsely chopped
½ cup heavy cream (35% cream)

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.

Part Five: Mango Cubes

(Note: It’s best to cubed the mangoes before assembling started.)

5 large Alphonso mangoes

1. Peel the skin of the mangoes with a vegetable peeler.
2. Cut the mangoes with a knife in the size of 1 inch cubes.
3. Set aside.

Assembling the Opera Cake

(Note: The finished cake should be served slightly chilled. It can be kept in the refrigerator for up to 1 day).

  • Jaconde
  • Honey syrup
  • Kiwi and Passionfruit buttercream
  • Mango cubes
  • White chocolate glaze
  • Some light green colored apricot glaze (optional)
  • 1 large Alphonso mango for decoration (optional)
  • 2 large kiwis for decoration (optional)
1. Line a baking sheet with parchment or wax paper.
2. 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.
3. Place one square of cake on the baking sheet and moisten it gently with the honey syrup.
4. Spread about one-third of the kiwi and passionfruit buttercream over this layer.
5. Place half of mango cubes onto the buttercream.

6. Top with the two rectangular pieces of cake, placing them side by side to form a square. Moisten these pieces with the honey syrup.

7. Spread another third of the buttercream on the cake and spread remaining mango cubes on the cake.
8. Then top with the third square of jaconde. Use the remaining honey syrup to wet the jaconde. Spread the remaining buttercream on top of the final layer of jaconde and then refrigerate until very firm (at least half an hour).

9. Make the white chocolate glaze and after it has cooled, pour/spread it over the top of the chilled cake. Refrigerate the cake again to set the glaze.
10. Once set, lightly brush top of the glaze with the green colored apricot glaze. Topped the cake with sliced mangoes and sliced kiwis.
11. Serve the cake slightly chilled. This recipe will yield approximately 20 servings.

As for the leftover jaconde, we assemble 4 layers of jaconde brushed with honey syrup, with slices of kiwis in between of the kiwi and passsionfruit buttercream, and topped off with the white chocolate glaze. The other opera cake to date; a Kiwi Opera Cake! We feasted on this baby and was fully satisfied with the result. The buttercream was creamy and not overly sweet, and we recommend that the Opera Cake should be eaten at room temperature. Or maybe slightly cold.

After a bite out of the Tr'opera Cake (Tropical Opera Cake), we make comparisons and came to a verdict that the Tr'opera Cake tasted way better than the Kiwi Opera Cake. The very sweet and juicy Alphonso mangoes were addictive, which turns out to be the main attraction of the cake. After combining the three tropical fruits; mango, kiwi and passion fruit (which is also Mom's favorite), there was no doubt that the thirst-quencher cake tasted refreshingly luscious, best eaten in hot and humid weather. However, we will definitely increase the amount of whipping cream in the white chocolate glaze as many had told us that the glaze is too sweet. Oh, here goes the meassage; Happy Belated Mom's Day, Mom! And to all mommies out there!