Pistachio Cake with Lemon Curd & Blackberries by Clementine Day
Clementine Day is an exceptionally talented, creative, multidisciplinary maker that runs Some Things I Like to Cook; an evolving project that draws a meaningful connection between food, people, and play.
We're big fans of everything Clem does, so asked her to create a celebratory cake to share with friends and loved ones during the festive season and special occasions.
"I love pistachios. I think they are my favourite nut. I especially love them salty, and that’s kind of what inspired this version of a pistachio cake. This cake leans gently into the sweet and salty thing that everyone has grown to love. The nutty pistachio cake with tart lemon curd and sweet blackberries is one of my favourite combos. You can substitute other berries here too, but I think blackberries are really the perfect friend to pistachios"
For the cake
340g self-raising flour
A couple of pinches of salt
4 tablespoons vegetable or other neutral oil
120g unsalted butter, room temperature
340g caster sugar
2 extra egg whites
2 teaspoons good quality vanilla paste or extract
160ml sour cream
For the Swiss meringue buttercream
4 egg whites
225g caster sugar
360g unsalted butter, softened
1 teaspoon good quality vanilla paste or extract
250g jar of lemon curd
Some spare pistachios, ground
For the cake
Preheat your oven to 180 C. Grease and line two 20-22cm cake tins.
In a food processor, blitz your pistachios into a pretty fine crumb. It doesn’t need to be completely powdery, small crumbs are fine. Combine the pistachio crumb with your self-raising flour and salt and set aside.
In a stand mixer fitted with a whisk attachment, combine room-temperature butter and oil until smooth. Add the caster sugar and beat on high speed for about 5 minutes, until fluffy and pale.
Add your eggs and egg whites, as well as your vanilla paste/extract and beat on medium-high for a further 3-5 minutes, until light and fluffy again.
Add sour cream and milk and mix for a few seconds, until just combined. Now remove the bowl from the stand mixer and add in dry ingredients, folding these in gently using a spatula, just until there are no streaks of flour remaining.
Divide the batter evenly between your two prepared cake tins and smooth out the tops. Bake in the oven for 25-30 minutes or until a knife or cake tester poked into the middle of the cake comes out clean.
Remove from the oven and let them sit in their tins for a couple of minutes. Then release and leave to cool completely on a wire cooling rack.
For the Swiss meringue buttercream
For the Swiss meringue buttercream, the first step here is to fill a medium-sized saucepan with about 2 inches of water and bring it to a simmer over medium heat.
Check your butter, if it’s not fully room temp/softened yet, put it somewhere warm or give it 15 seconds in the microwave until it is. It should be soft enough that you can squish it flat between your fingers with little effort, but it should not be warm!
Now combine your sugar and egg whites in the bowl of your stand mixer. Combine well with a spatula so that no clumps of dry sugar remain.
Place the stand mixer bowl over the top of the saucepan of boiling water, ensuring that the bottom of the bowl is not touching any water. We just want the steam to warm the bowl. Mix constantly with your spatula and test frequently by pinching a small amount between your fingers and rubbing to feel for grainy sugar. Keep going until you can no longer feel any sugar granules, no more sandiness. The sugar is now dissolved, and you can remove this from the heat.
Place the bowl onto your stand mixer and with the whisk attachment on a high speed, whisk the egg whites and sugar until stiff peaks form. It will be the softest, most luscious meringue you’ve ever tasted, so be sure to give it a little taste test.
Now add your butter, one thumb sized chunk at a time, whilst beating on a medium/low speed. Let each addition of butter blend into the meringue before adding the next blob. At first, it will feel like it’s made the mixture a bit gloopy, but by the time you add all the butter, you should have the most glossy, gorgeous buttercream you’ve ever seen. Add your vanilla paste and beat just enough to combine evenly.
If your buttercream starts to split, which will appear as an extra grainy, bubbly-looking mixture, try to establish whether it is too hot or too cold. You’ll get an inkling. Not completely sure if your butter was soft enough? Is your mixer bowl still warm from being on the steam? Maybe the weather is particularly warm or cold today? From there, wrap the mixer bowl with either a heat pack or an ice pack, depending on your circumstances, and within a few beats, you should start to see it coming smooth again.
Choose your serving plate and centre one of the cakes onto it. Use a piping bag to pipe a ring of buttercream around the top edge of the cake, creating a bit of a wall or barrier for the lemon curd and blackberries which will fill it. If you don’t have a piping bag, just spoon it on and spread the buttercream to create the same kind of wall.
Spoon your lemon curd in and spread it around evenly, top generously with about two-thirds of your blackberries, be generous here, don’t leave much open space.
Place the next cake on top and cover the whole thing with the rest of the buttercream. Try to avoid getting too particular about it, it can be a never-ending journey.
Decorate the top with the remaining blackberries, any little dollops of lemon curd that may remain in the jar, and some crumbs of pistachio and flowers, if you want to.
This cake is best eaten at room temperature but is best stored in the fridge. So be sure to thaw it out to room temperature before enjoying a slice!