Gluten-Free Strawberry Basil Cake

If you would like to switch up your regular Strawberry Cake then this unique variation always causes a bit of excitement whenever I serve it. It's basically a Strawberry 'Sweet Pesto' Cake. The sweet pesto is just that, a verdant basil pesto without the garlic but with honey instead. It still retains pine nuts which go wonderfully with strawberries and olive oil for its peppery notes.

The cake is filled with a fresh strawberry basil jam which is quickly set with chia seeds instead of sugar. A teaspoon of freeze-dried strawberries stirred in is optional but I had them to hand for the strawberry buttercream so in they went. Freeze-dried berries are a brilliant way of injecting a pure intense fruity flavour and here it really amps up the jam. They are also invaluable in buttercreams as they mean you won’t lose any of the structural integrity of the buttercream like you would with a fresh strawberry puree or add any further sweetness if you were to use a strawberry jam.

Ingredients needed

Vanilla sponge

Caster sugar. It’s a fine white baking sugar available in the UK. Regular white granulated sugar can be substituted.

Lemon. Make sure it is unwaxed and organic otherwise you need to scrub off the wax.

Unsalted butter. We need unsalted so we can control the salt content of the recipe. Make sure it is at room temperature.

Eggs. This recipe uses medium size, about 60g each with shell (50g each without shell). These are often classified as large eggs in the US. I recommend weighing your eggs to ensure the correct amount.

Milk. Using whole milk or a plant based milk is fine.

Vanilla extract. You don’t need to use the best quality vanilla extract here as there's already a lot going on with the flavours and it won't make a difference. A supermarket brand is just fine.

Gluten-Free Flour – FTL Blend. This recipe uses my Homemade Gluten-Free All Purpose Flour which works really well here as the flour ratio has been carefully tested to ensure the mix between wholegrain flours and starchy flours is balanced. This also means we don’t need to use xanthan gum as the blend is strong enough and produces a well structured and textured bake which can hold together without needing any extra binders. This flour blend is a mix of 4 different flours: Sweet rice flour (glutinous rice flour), Sorghum flour, Oat flour, Tapioca flour (tapioca starch).

There are plenty of flour substitution tips ideas if you click on the original post for this homemade flour mix.

Baking powder. A leaving agent which causes the cake to rise and become light and fluffy. Do check your baking powder is gluten-free before use.

Salt. I like to use kosher salt in my baking as it has a round gentle flavour. Using salt in your baked goods lifts and sharpens all the other flavours.

Strawberry Basil Honey Jam

• Strawberries
• Lemon juice
• Honey
• Fresh basil
• Ground chia seeds
• Freeze-dried strawberry powder (optional)

Sweet Pesto

• Fresh basil
• Honey
• Olive oil
• Pine nuts
• Parmesan I actually don't use parmesan in this recipe anymore. You could but it doesn't need it as there's so much going on with the flavour anyway.

Swiss Meringue Buttercream

• Egg whites (120g)
• Caster sugar
• Unsalted butter
• Freeze-dried strawberry powder
• Sweet pesto (as above)

How do you make Swiss Meringue Buttercream?

1. Heat the egg whites and sugar in a bain marie or double boiler, whisking all the time.
2. When the sugar has completely melted and the temperature reached 71°C then remove from the heat and immediately pour into a stand mixer.
3. Whisk on a medium setting for about 10 minutes until a glossy meringue has formed and the temperature has lowered to about 32°C.
4. Change the whisk attachment to a paddle beater and beat on low adding the butter one cube at a time.
5. Once all the butter has been added and the buttercream looks beautifully smooth split the buttercream ¾ and ¼.
6. Mix the strawberry powder with the ¾ amount of buttercream and the sweet pesto with the ¼ amount.

Swiss Meringue Buttercream Tips

• The temperatures here are important. If you have made SMB a few times then you can intuit when the sugar has melted into the egg whites or when the meringue has cooled enough to add the butter. However for newbies a sugar thermometer is invaluable.
• The butter must be at room temperature before you add it. Slightly soft to the touch but not melty.
• If your butter is too cold then just keep on mixing the buttercream once it’s all added, the butter will soon warm and melt into the buttercream. If that doesn’t work then warm slightly over a bowl of boiling water. Once the edges of the buttercream start to soften then start whipping again off the heat.
• If your butter is too warm place in the fridge for 15 minutes to chill then try re-whipping it.
• As you are adding the butter your buttercream will look a bit curdled. This is absolutely normal. Keep on mixing the buttercream and don’t lose faith, it will always come together in the end.
• If your buttercream does not come together and looks too soupy that means your butter was too warm – see above on how to fix.