Vegan Diva Cake

Hi baking friends!

This is something slightly different to my usual baking shenanigans but today I decided to veganise a recipe from one of my all-time favourite bakers – Zoe bakes!  Zoe is an absolutely incredible baker and her instagram is full of amazing desserts that I’m fully in awe of! 

One cake that stood out to me on her feed was this GORGEOUS blackberry opera torte that she named the “Diva cake”! What a fabulous name for an absolute knock-out dessert! This delicious-looking creation is a spin on the classic Opéra gâteau with a lot more layers, a blackberry buttercream instead of the classic coffee flavours and a glossy layer of Italian meringue on top! Please go check out her recipe post here!

Now for a vegan this presents quite the challenge as the original recipe includes eggs in 3 out of 4 of the elements and butter/cream/dairy in some of the others. If you’re familiar with my page you’ll know I make vegan meringue all day every day so I’m not too worried about the Italian meringue topping or the swiss meringue buttercream but the one near-impossible hurdle is the Joconde sponge!

Now you might be thinking – Tom can’t you just fold whipped aquafaba meringue into a vegan almond cake batter like the non-vegan version and bake that? I wish I could but unfortunately the one flaw of aquafaba when compared to egg whites is that it’s water-based so it does not solidify under heat like egg whites. This will almost always result in a soggy bake. 

Currently I have not found any vegan method to master Joconde sponge but I do have a workaround! For this recipe I will be combining my recipe for a classic vanilla vegan cake with some almond meal and almond extract to emulate some of that fragrant almond flavour and texture of a Joconde sponge. 

Aquafaba features quite heavily in this recipe so if you don’t have too much experience I would definitely recommend you try something slightly less advanced – all my aquafaba recipes are collected here! You’ll need 3 cans for this recipe.

On that note I will try to be as descriptive as possible in my recipe but if you want some extra tips I would gladly recommend you check out Gretchen’s Vegan Bakery for her vegan swiss meringue buttercream recipe as she’s got a full recipe page and video tutorial dedicated towards it. After tasting this dessert, that light and silky swiss meringue filling is maybe my favourite element so it’s important to nail it!

This recipe is certainly not easy but I think it has that wow factor and it’s definitely worth the effort!

Some final notes on the ingredients used in this recipe:

I have mentioned in the ingredients list to use organic soy milk with no additives. From experience, it’s a lot safer to use a plant milk with no additives because they can interfere with the chemistry of the bake.

I have also tried to use ingredients that most readers would have access to. If you’re a more advanced baker I would suggest making smart substitutions if you think it’ll work in your favour. A good example is replacing lemon juice with cream of tartar as the meringue likes to be dry and adding extra moisture risks spoiling it.

Lastly, when I mention “vegan butter” I refer to any plant-based margarine/spread that contains at least 75% fat. Any less and you’ll introduce uninvited extra moisture into the bake.

For this recipe you’ll need:

• offset spatula
• candy thermometer
• stand mixer
• handheld blowtorch
• 2 flat baking trays

One final important note: the sponge cake recipe below will yield two very very thin layers of cake across 2 small baking sheets (ideal for an opera cake as we want really elegant thin layers). However, if you have medium to large baking pans this batter might not be enough to cover two trays so I would suggest making the sheet cake twice or doubling up the recipe.

Let’s get into the recipe!!! (Posting as text and a printable version below)

Almond Sponge Cake

• 250 ml organic soy milk (no additives + room temp)
• 2 tsp apple cider vinegar
• 180g all purpose flour
• 40g almond flour
• 160g granulated sugar
• ½ tbsp baking powder
• ½ tsp baking soda
• 75g vegetable oil
• 1 tbsp vanilla extract (optional)
• 1 tbsp almond extract (optional)
• pinch of salt

Swiss Meringue Buttercream

• 150ml aquafaba (from 1 can)
• 100g caster sugar
• 1 tsp vanilla extract (optional)
• 90g icing sugar
• 1 tsp lemon juice
• 160g vegan butter (room temp)
• 100g vegetable shortening (room temp)
• 80g blackberry preserve (optional)

Chocolate Ganache

• 250g dark chocolate (55% cocoa solids)
• 200ml soy cream

Decorative Italian Meringue

• 100ml aquafaba reduced
• 180g granulated sugar
• 50ml water
• 2 tsp lemon juice
• 1 tsp vanilla extract (optional)

Almond sponge cake:

Pre-heat oven to 180C (350F).

Line two baking sheet pans with parchment and (optionally) spray with oil so the layers come out easier.

Mix together the soy milk with the apple cider vinegar and set aside for 10 mins to curdle.

Meanwhile sieve and mix together all the dry ingredients (flour, almond flour, sugar, baking powder, soda and salt).

Add the vanilla extract, almond extract and oil to the curdled soy milk and whisk together.

Finally, lightly whisk the wet ingredients into the dry ingredients until the batter is smooth (no longer than 30 seconds).

Pour the batter into the two baking trays. You want the layers to be exceptionally thin so use an offset spatula to smooth it out flat.

Bake at 180C for 15 minutes. Use a toothpick to check they are cooked the whole way through. Rotate at the 10 min mark if necessary.

Take the cakes out of the oven to chill for 2 hours.

Meanwhile prepare the reduced aquafaba for the Italian meringue. Pour the liquid from 2 cans of chickpeas into a measuring jug – you’ll need approximately 300ml. Pour into a pan and reduce on low heat for 15 minutes.

Leave to cool for the remainder of the 2 hours.

Chocolate Ganache:

Heat the soy cream up to a simmer. Take it off the heat and add the chopped chocolate. Gently stir the chocolate until it’s fully melted.

Spoon the ganache onto both layers of the sponge sheet. Use a spatula to make sure the layer is completely even.

Swiss meringue buttercream:

Pour the liquid from 1 can of chickpeas (150ml) into a saucepan with the 100g of caster sugar.

Bring to a simmer for 10 minutes until all the sugar is dissolved and then pour into a stand mixer bowl to cool. This will need at least an hour.

Once the aquafaba sugar mix is cool, whip the aquafaba on medium-high until firm peaks.

Add the 1 tsp lemon juice and icing sugar (one spoon at a time).

Add the (softened) vegan butter and margarine to the mix one cube at a time. Each time the mixture becomes soupy or flat, wait for it to whip back to normal before adding the next cube.

Add the vanilla and blackberry preserve and whip for 1 minute.

Final Construction:

Spoon the buttercream onto the sponge + chocolate layers. Use an offset spatula to flatten the layers perfectly.

Chill both layers in the freezer for 15 minutes (or the fridge for 1 hour). Trim the edges of the cake if ganache or buttercream has spilled down the sides.

Cut each of the cake layers into 3 rectangle pieces and stack them on top of each other.

Place the blackberries on top.

Italian meringue:

Put the reduced aquafaba in a stand mixer and whip on medium-high. You will need it to be at firm peaks by the time the sugar syrup is ready.

Add the lemon juice.

Meanwhile place 180g caster sugar + 50ml of water in a pan on medium-low heat. Use a candy thermometer and slowly raise the temperature to 240F.

Do not mix the sugar too much, or even at all if possible, or it will crystalise and become unusable.

Once 240F is reached, slowly pour the hot sugar syrup down the side of the bowl into the whipping meringue.

Keep whipping the meringue for a further 10-15 minutes so it can cool down.

Pipe or spoon the meringue onto the blackberries.

Torch the meringue with a handheld blowtorch.

Serve!

5 from 1 reviews

Vegan Diva Cake

June 7, 2020

Servings: 12

Prep: 5 hr

Cook: 15 min

Total: 6 hr 15 min

Difficulty: Hard

Print This

This blackberry opera torte is the show-stopper to end all show-stopper desserts! Layers of creamy chocolate ganache sandwiched between silky smooth swiss meringue buttercream and almond sponge.

By: Project Vegan Baking

Ingredients

• Almond Sponge:
• 250ml organic soy milk (no additives + room temp)
• 2 tsp apple cider vinegar
• 180g all purpose flour
• 40g almond flour
• 160g granulated sugar
• ½ tbsp baking powder
• ½ tsp baking soda
• 75g vegetable oil
• 1 tbsp vanilla extract (optional)
• 1 tsp almond extract (optional)
• pinch of salt
• Swiss Meringue Buttercream:
• 150ml aquafaba (from 1 can of chickpeas)
• 100g caster sugar
• 1 tsp vanilla extract (optional)
• 90g icing sugar
• 1 tsp lemon juice
• 160g vegan butter (room temp)
• 100g vegetable shortening (room temp)
• 80g blackberry preserve (optional)
• Chocolate Ganache:
• 250g dark chocolate (55% cocoa solids)
• 200ml soy cream (can be substituted with soy milk but use 160ml instead)
• Decorative Italian Meringue:
• 100ml aquafaba reduced
• 180g granulated sugar
• 50ml water
• 2 tsp lemon juice
• 1 tsp vanilla extract (optional)

Directions

• Step 1 Almond sponge cake: Pre-heat oven to 180C (350F).
• Step 2 Line two baking sheet pans with parchment and (optionally) spray with oil so the layers come out easier.
• Step 3 Mix together the soy milk with the apple cider vinegar and set aside for 10 mins to curdle.
• Step 4 Meanwhile sieve and mix together all the dry ingredients (flour, almond flour, sugar, baking powder, soda and salt).
• Step 5 Add the vanilla extract, almond extract and oil to the curdled soy milk and whisk together.
• Step 6 Finally, lightly whisk the wet ingredients into the dry ingredients until the batter is smooth (no longer than 30 seconds).
• Step 7 Pour the batter into the two baking trays. You want the layers to be exceptionally thin so use an offset spatula to smooth it out flat.
• Step 8 Bake at 180C for 15 minutes. Use a toothpick to check they are cooked the whole way through. Rotate at the 10 min mark if necessary.
• Step 9 Take the cakes out of the oven to chill for 2 hours.
• Step 10
• Step 11 Meanwhile prepare the reduced aquafaba for the Italian meringue. Pour the liquid from 2 cans of chickpeas into a measuring jug – you’ll need approximately 300ml. Pour into a pan and reduce on low heat for 15 minutes. Leave to cool for the remainder of the 2 hours.
• Step 12 Chocolate Ganache: Heat the soy cream up to a simmer. Take it off the heat and add the chopped chocolate. Gently stir the chocolate until it’s fully melted.
• Step 13 Spoon the ganache onto both layers of the sponge sheet. Use a spatula to make sure the layer is completely even.
• Step 14 Swiss meringue buttercream: Pour the liquid from 1 can of chickpeas (150ml) into a saucepan with the 100g of caster sugar.
• Step 15 Bring to a simmer for 10 minutes until all the sugar is dissolved and then pour into a stand mixer bowl to cool. This will need at least an hour.
• Step 16 Once the aquafaba sugar mix is cool, whip on medium-high until firm peaks.
• Step 17 Add the 1 tsp lemon juice and icing sugar (one spoon at a time).
• Step 18 Add the (softened) vegan butter and shortening to the mix one cube at a time. Each time the mixture becomes soupy or flat, wait for it to whip back to normal before adding the next cube.
• Step 19 Add the vanilla and blackberry preserve and whip for 1 minute.
• Step 20 Final Construction: Spoon the buttercream onto the sponge + chocolate layers. Use an offset spatula to flatten the layers perfectly.
• Step 21 Chill both layers in the freezer for 15 minutes (or the fridge for 1 hour). Trim the edges of the cake if ganache or buttercream has spilled down the sides.
• Step 22 Cut each of the cake layers into 3 rectangle pieces and stack them on top of eachother.
• Step 23 Place the blackberries on top.
• Step 24 Italian meringue: Put the reduced aquafaba in a stand mixer and whip on medium-high. You will need it to be at firm peaks by the time the sugar syrup is ready.
• Step 25 Add the lemon juice.
• Step 26 Meanwhile place 180g caster sugar + 50ml of water in a pan on medium-low heat. Use a candy thermometer and slowly raise the temperature to 240F.
• Step 27 Do not mix the sugar too much, or even at all if possible, or it will crystalise and become unusable.
• Step 28 Once 240F is reached, slowly pour the hot sugar syrup down the side of the bowl into the whipping meringue.
• Step 29 Keep whipping the meringue for a further 10-15 minutes so it can cool down.
• Step 30 Pipe or spoon the meringue onto the blackberries.
• Step 31 Torch the meringue with a handheld blowtorch.
• Step 32 Serve!