How to Make Opera Cake – Soft, Smooth, Fluffy, and Irresistibly Delicious Opera Cake

How to Make Opera Cake

• 1

  Make coffee syrup

  Add 130g of hot water to 7g of instant coffee, stir in 30g of sugar, then add 6g of Kahlua and mix the mixture well, keeping the coffee warm.

  
• 2

  Melt chocolate for the Ganache

  Heat 125g of heavy cream until you see it starting to boil around the edges of the pot, then turn off the heat, remove it from the stove, and add 125g of dark chocolate. Let the chocolate melt naturally for about 1 minute, then use a spoon to gently stir until the chocolate is completely melted and combined with the cream.

  
• 3

  Whipping Egg Whites

  Put 3 eggs and 80g of sugar into a mixing bowl and whip the eggs using a double boiler method. Place a pot of hot water underneath and the bowl of eggs on top (it is advisable to use a thick bowl to avoid overheating that could cook the eggs), with the water underneath at a temperature of about 40 – 50 degrees Celsius. Whip until the temperature of the eggs reaches about 40 degrees Celsius, then remove.

  Use an electric mixer until the eggs reach a thick, smooth, and creamy state with an off-white color, and when you lift the whisk, the egg mixture flows like a ribbon, then stop.

  Note:

  The eggs must be at room temperature; if the eggs are taken from the refrigerator, let them warm up before performing this step. Whip the eggs in one direction, and the eggs must be whipped to a thick state; otherwise, when mixing with flour, the air bubbles in the eggs will easily break, causing the cake to rise poorly.

  Warming the eggs will help them whip quickly and stabilize their structure, resulting in a better rise for the cake. However, you can also whip the eggs without warming them up.

  
• 4

  Mixing the Cake Batter

  Sift 100g of almond flour and 30g of all-purpose flour into the whipped egg mixture, and gently fold the mixture by scooping and lifting from the bottom. Mix until you achieve a homogeneous mixture.

  Note:

  When mixing the ingredients together, it is advisable to mix very gently or use the folding method (mixing by turning and lifting from the bottom) and not to overmix to avoid breaking too many air bubbles, which can prevent the cake from rising beautifully.

  
• 5

  Whipping Egg Whites

  Add a pinch of salt to 100g of egg whites, whip the egg whites on low speed for about 45 seconds until frothy like soap.

  Divide 40g of sugar into 3 parts, gradually add each part one at a time, and whip until dissolved. Whip each portion of sugar for about 30 seconds on low speed before adding the next portion.

  When adding the last portion of sugar to the egg whites, increase the mixer speed to high, and whip the egg whites until soft peaks form, with a creamy texture, the mixture is sticky, shiny, and smooth. When you lift the whisk, it should create a droopy peak.

  Note:

  • The egg whites, whisk, and mixing bowl must be clean, free from any fats such as oil, grease, butter, or egg yolks.
  • Avoid whipping the egg whites too stiff, as it will be difficult to mix evenly with the yolk mixture.
  • Whip in one direction to avoid breaking the air bubbles.
  • Salt will help the egg whites whip faster, but using too much will alter the cake’s flavor, so for safety, you can use cream of tartar.

  See more details: How to whip egg whites

  
• 6

  Mix the flour with whipped egg whites

  Take 1/3 of the egg whites and add them to the mixture of flour and egg yolks, mixing well by folding and lifting from the bottom to avoid breaking the air bubbles, which helps the cake rise beautifully. Mix until the two components are well combined.

  Add the yolk mixture to the remaining egg whites and continue to fold and lift from the bottom until you achieve a smooth and homogenous mixture.

  Add 20g of melted butter and 5g of vanilla extract, and gently mix to combine until the mixture is uniform.

  
• 7

  Bake the cake

  Preheat the oven to 200 degrees Celsius for 15 minutes to stabilize the temperature.

  Prepare a mold lined with parchment paper and pour the mixed batter into it. Spread evenly and gently tap the mold on the table to break any large air bubbles. You should not pour the batter too thickly, as this will result in a longer baking time and the cake may collapse after baking. It is advisable to choose a square mold about 3 cm thick to help the cake bake quickly and also make it easier to cut after baking.

  Place the cake in the oven at 190 degrees Celsius for 8 – 10 minutes. Remove the cake and let it cool completely.

  Note: You should not pour the batter too thickly, as this will result in a longer baking time and the cake may collapse after baking. It is advisable to choose a square mold about 3 cm thick to help the cake bake quickly and also make it easier to cut after baking.

  
• 8

  Making coffee buttercream

  Dissolve 5g of coffee and 6g of Kahlua with 6g of hot water to get a concentrated coffee mixture.

  Take 180g of butter at room temperature and cut it into small pieces.

  Add 30g of water and 75g of sugar into a pot and then place it on the stove over medium heat until it boils and thickens slightly. If you have a thermometer, the sugar should reach 118 degrees Celsius.

  Beat 3 egg yolks at high speed until they are slightly fluffy, then gradually add in the melted sugar mixture. Keep the speed high and beat the yolks until they reach a fluffy, smooth state, with an ivory color, thick, shiny, and when you lift the whisk, the mixture flows like a ribbon, then stop.

  Gradually add the soft butter into the egg-sugar mixture while beating at low speed, continue until all 180g of butter is incorporated.

  When the butter has melted and blended with the yolk mixture, add the concentrated coffee and continue to beat at low speed until all ingredients are well mixed.

  Note:

  • Avoid letting the sugar turn caramel color, otherwise the cream will not look appealing.
  • Do not let the sugar touch the whisk as it will cause the sugar to splatter.
  • It is recommended to use a narrow-bottom bowl to whip the buttercream as it will yield faster and more stable results, and whip the buttercream in one direction.

  ​See more details: How to make buttercream for decorating cakes simply from egg whites

  

  

  
• 9

  Layering the cake

  Divide the cooled cake into 4 equal parts.

  Use a brush to spread coffee syrup on the surface of the first layer of cake, spreading until the cake absorbs the syrup evenly. Add the Ganache on top and use a knife to smooth it out across the cake surface. Stack the second layer on top, brush with coffee syrup, and add the butter cream on top, smoothing with a knife.

  Continue stacking the cake layers and do the same, the third layer will have coffee syrup and Ganache like the first layer, and the fourth layer will have coffee syrup and coffee butter cream.

  Once finished, place the cake in the refrigerator for 1 hour.

  
• 10

  Making the chocolate glaze and finishing the cake

  Melt 100g of dark chocolate by placing a bowl over a pot of hot water, when the chocolate is completely melted, add 15g of cooking oil and mix well to cool the chocolate to room temperature.

  Once the cake has been chilled, take it out and pour the chocolate over it, using a knife to smooth it out to finish.

  

  
• 11

  Final Product

  Cut the cake into bite-sized pieces and decorate as desired.

  The cake has an eye-catching layered design and a flavor blend of chocolate and coffee. When eaten, the coffee flavor merges with the sweet chocolate aroma combined with rich, fragrant buttercream, creating a wonderful cake that is sure to captivate food enthusiasts.

  The cake can be served at tea parties or gatherings, making it truly wonderful.

  Some notes when making opera cake:

  • The cake layers must be completely cool before adding the cream, just as the chocolate glaze should be at room temperature before being applied to the cake.
  • If the cake layers are left overnight and absorb moisture, simply wait for the cake to dry, then wrap it and place it in the freezer; when ready to use, defrost it and it will be fine.
  • The eggs used for the cake must be fresh; otherwise, the whipped eggs will not be fluffy. Beating the eggs must be done correctly; otherwise, the cake will not rise well and may have an unpleasant smell.
  • Leftover cake can be stored in the refrigerator and consumed within about 2 – 3 days.