Vanilla, Passionfruit and Raspberry Dome Cake

This is my first time making a dome cake – I’ve been seeing them all over my feed lately. Whilst it’s not perfect, I’m still pretty pleased with how it turned out.

For the cake flavour and fillings, I’ve chosen a vanilla sponge filled with swiss meringue buttercream, passionfruit curd and raspberry jam. Of course, you can simplify it by using just one filling and doubling that portion of the recipe below. Personally, I am more partial to the passionfruit.

I’ve mentioned this before, but I never used to be fond of swiss meringue buttercream. Maybe because the versions I’ve tried had this odd, greasy meringue texture. I assure you, this recipe is not that, and is far less sweeter than American buttercream.

This gluten-free cake recipe is one I’ve shared countless times in the past. I keep meaning to simplify the recipe, but it just works so well everytime. There are some important baking notes as usual, because I believe it’s important to understand the recipe in order to succeed.

• This is a butter-based cake recipe involving the creaming method. To incorporate air and yield a light cake, it is important to cream the butter and sugar for at least five minutes on high speed. Do not rush this step.
• Since the butter is at room temperature, the eggs should also be at room temperature. If you forget to take your eggs out of the fridge, you can place your eggs in hot (not boiling) water for 5 minutes.
• This specific blend and ratio of flours is pivotal in achieving that light yet moist texture. It is very important for the white rice flour to be super fine. I prefer to develop recipes with the individual flours rather than using a store-bought GF flour blend, because each brand has a different mix of flours and may not necessarily work. Please don’t be intimidated by the amount of ingredients.
• After the dry ingredients are added, thebatter will appear quite thick. To loosen the batter, I prefer to use water instead of milk. Once the water is added, it is important to beat the batter on medium-low speed for about 20 seconds, as it will visibly become fluffier and more emulsified.

If you’d like to make the cake layers ahead of time, I recommend wrapping them tightly in plastic wrap and storing in an airtight container. The fillings can be made in advance as well.

To create the dome shape, I stack all three cake layers on top of each other, then use a serrated knife to carefully carve the sides of the top layer (and part of the second), giving the cake its rounded finish. Once the cake is assembled and filled, I do a bit more trimming to refine the dome shape before the crumb coat.

You can decorate the cake however you like. I went with a vintage piping design and finished it with sugared grapes (recipe here). It would’ve made more sense to use fresh raspberries or incorporate passionfruit somehow, given the fillings, but I didn’t have any on hand.

I wasn’t entirely happy with the photos, as I couldn’t get the lighting quite right with the white frosting. Have a great week, and let me know if you have any questions!

Vanilla, Passionfruit & Raspberry Cake

Makes a three layer 15cm cake. Raspberry filling adapted from Sally’s Baking Addiction.

Ingredients

Vanilla Cake

• 170g unsalted butter, room temperature
• 170g caster sugar
• 1.5 tbsp neutral oil (e.g. canola, vegetable)
• 3 eggs, room temperature
• 1/2 tsp vanilla extract
• 60g almond meal
• 90g white rice flour
• 30g potato starch
• 15g tapioca starch
• 2 tsp baking powder
• 3/4 tsp xanthan gum
• 3-5 tbsp water

Passionfruit Curd

• 2 egg yolks
• 55g caster sugar
• 60g passion fruit pulp
• Pinch of salt
• 45g unsalted butter, cubed

Raspberry Filling

• 85g frozen or fresh raspberries
• 17g caster sugar
• 1/4 tsp lemon juice
• 3g cornflour
• 2 tsp water

Swiss Meringue Buttercream

• 135g egg whites (about 4 large eggs)
• 270g caster sugar
• 370g unsalted butter, room temperature and cut into 2cm cubes
• 1 tsp vanilla extract

Method

Vanilla Cake

1. Preheat the oven to 180°C. Grease and line two 15cm cake tins with parchment paper.
2. In the bowl of a stand mixer fitted with a paddle attachment, cream together the butter and sugar on high speed until light and pale in colour, about 5 minutes. Add the eggs, one at a time, beating well in between each addition. Add the vanilla extract.
3. In a separate bowl, combine the almond meal, rice flour, potato starch, tapioca starch, baking powder and xanthan gum. Add this to the butter and sugar mixture, and mix on low speed until just combined. Add the water, starting with 3 tbsp, and mix on medium-low speed until fluffy and a smooth batter has formed, about 30 seconds. If the batter feels too thick, add more water.
4. Divide the batter evenly between the prepared cake tins (around 230g per tin). Bake for 23-27 minutes, or until golden and the cakes spring back when lightly touched. Allow the cakes to cool in tins for about 20 minutes, then transfer onto a wire rack to cool completely.

Passionfruit Curd

1. In a small saucepan, combine the egg yolks, caster sugar, passionfruit pulp, and salt. Whisk over medium heat until slightly thickened and sugar has dissolved.
2. Add the butter, a few cubes at a time, and simmer for about 3-5 minutes until thickened and well emulsified.
3. Cover and refrigerate until cool.

Raspberry Filling

1. In a small saucepan, combine the raspberries, sugar and lemon juice. Bring to a boil, over medium-low heat, stirring occasionally until the raspberries have broken down.
2. Whisk together the cornflour and water. Add half of this slurry to the raspberries, and mix until thickened. It should be thick enough at this point but, if not, add the remaining slurry mixture.
3. Transfer the filling into a jar or container. Cover and refrigerate until cool.

Swiss Meringue Buttercream

1. In a standmixer bowl, combine the egg whites and sugar. Place the bowl over a pot of simmering water, ensuring the bottom of the bowl doesn’t touch the water. Whisk the mixture constantly until the sugar has dissolved. Test by rubbing the mixture between your fingers and you should feel no granules of sugar. It should heated to around 71-74°C.
2. Remove from the heat. Place the bowl onto your stand mixture fitted with a whisk attachment. Whip on medium-high speed for 15 minutes or until the bowl feels cool to the touch.
3. On low speed, add the butter a few cubes at a time. The butter should be completely incorporated before adding the next lot of butter. To do this, beat on medium speed in between each addition.
4. When all of the butter has been added, beat the buttercream on medium-high speed for 5-8 minutes.
5. Switch the whisk to a paddle attachment, then add the vanilla extract. Finally, beat on low speed for 5 minutes.

Decorating and Assembly

1. Trim and level the cooled cakes, removing the skin that has formed on top. To create the dome shape, stack all three cake layers on top of each other, then use a serrated knife to carefully carve the sides of the top layer (and part of the second), giving the cake its rounded finish.
2. Spread a a small amount of buttercream onto your serving plate, then place your first layer of cake onto the plate.
3. Spread a generous amount of buttercream onto the cake, then pipe a dam around the edge of cake using a piping bag fitted with a plain round nozzle. Fill the centre with passionfruit curd. Place the second layer of cake on top. Repeat this process, creating a dam for the raspberry filling. Make any trimmings needed to refine the dome shape.
4. Spread a thin layer of buttercream around the sides and all over the cake to create a crumb coat. Place the cake in the fridge for 30 minutes, or until the crumb coat is firm to the touch.
5. Optional: I recommend setting aside some of the buttercream for piping. Then, to the remaining portion, microwave a quarter of this buttercream for about 20 seconds until melted. Add this mixture to the buttercream and mix on low speed until just combined. This will loosen the frosting so it’s more silky and spreadable for decorating.
6. Use the loosened buttercream for the final coat. Use the thicker frosting for piping and decorating however you like. Finish with flowers or fruit.