Clem Day’s Brown Butter Vanilla Cake Filled With Chocolate Sour Cream Ganache And Boozy Blackberries
This cake is a celebration in its own right – no need for a birthday, milestone, promotion, engagement, or anything else of the like! It’s delicious, fun to assemble and the boozy blackberries are a wonderful treat, too.
I really want you to have fun with this cake, maybe you’ll learn a couple of new techniques along the way, overcome your fear of Swiss meringue buttercream, realise that sour cream ganache is easier than you expected or pour yourself a glass of brandy to enjoy while the blackberries bathe in it. If you’re a nervous baker, maybe start with the glass of brandy, put some of your favourite tunes on, set the mood – this is meant to be a fun activity, just as fun to make as it is to eat!
Cake (2 layers):
300g unsalted butter
375g self-raising flour
330g caster sugar
1 teaspoon salt
4 large eggs
2 teaspoons good vanilla bean paste
Chocolate sour cream ganache:
300ml sour cream, room temp
180g 40%-60% cocoa dark chocolate
Swiss Meringue buttercream:
340g unsalted butter, softened and cut into thumb sized chunks
1 cup caster sugar
½ cup egg whites (approximately 3-4)
1 teaspoon good vanilla bean paste
2 punnets of fresh blackberries
3-4 tablespoons of brandy
1 jar of good quality blackberry jam
Before you begin, I highly recommend baking your cake layers the day/night before, for ease of assembly the following day.
For the brown butter vanilla cakes:
First thing we’re going to do is brown our butter. Add your butter to a medium saucepan and over a medium/low heat, simmer your butter, agitating the pot occasionally and scraping down the bottom with a spatula regularly. Once it has simmered a bit, it will begin to foam. Now start to stir constantly. Once your butter reaches a lush caramel brown colour and starts to smell nutty, pour it into a small bowl and place into the freezer to solidify again. This will take about 30-45 minutes.
After your butter has solidified in the freezer, preheat your oven to 180 C and prepare your oven racks so that you will fit both cakes into the most central position possible. Remove your butter from the freezer to bring it back towards room temperature.
Grease and line two 22-24cm spring form cake tins with baking paper.
Weigh out and sift your flour into a small bowl and set aside. Combine your milk and vanilla into a small jug and set this aside, too.
Don’t start the next step until your butter has softened, ready to beat. With an electric beater, beat sugar and softened brown butter until combined. Increase the speed to high and beat for 5-8 minutes, until very pale and creamy. Reduce the speed to low and add the eggs, one at a time, beating well between each.
Alternately add your dry (flour) and wet (milk and vanilla) ingredients to the mixer, mixing on low between each addition until just combined, before adding the next. Once everything is added, beat just enough until smooth, making sure to scrape down the sides of the bowl with a spatula.
Divide your batter between your two prepared tins and smooth out the top.
Cook in centre position of oven for 30-35 minutes or until a skewer or cake tester comes out clean when poked into the middle of your cake/s. Every oven is different so don’t fret if you need to cook for longer than I’ve suggested, there are lots of variables here (oven, cake tin size etc.) so the best thing to do is go with the clean cake tester approach. Don’t worry about poking too many holes in the cakes while testing, it will all be covered with buttercream anyway.
Do not do anything else until the cakes are absolutely cooled, to the core. If baking your cakes the day before, cover well with foil and store in the fridge overnight in an airtight container. Bring out of the fridge first thing the next morning so they can come back to room temperature.
For the boozy blackberries:
Take your blackberries and pop them in a bowl with the brandy, leave them to sit for 3-4 hours before assembling the cake.
For the Swiss meringue buttercream:
This is a combination of words that immediately makes novice bakers think “hell no – that’s too advanced for me, I haven’t even mastered regular old buttercream”. Well let me tell you, this is easier than regular old buttercream. Just trust me on this and come along for the ride.
First step here is to bring a small/medium saucepan of water to the boil.
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.
Now combine your sugar and egg whites into 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. 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 the time you add all the butter, you should have the most glossy, gorgeous buttercream you’ve ever seen.
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? 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.
For the chocolate sour cream ganache:
Start by simply melting your chocolate, either in the microwave or over a double boiler until completely melted and smooth. If using the microwave, please do it in 30 second intervals, stirring in between, to ensure that you don’t burn your chocolate.
Now grab a whisk and your sour cream. Add the sour cream into the bowl of melted chocolate and whisk vigorously to combine. It should become smooth and moussey. That’s all for the ganache. If you can see little, tiny chunks of chocolate, your sour cream might have been a bit too cold. Pop the bowl into the microwave for 10-15 seconds intervals and whisk again, until smooth.
To assemble the cake:
Start by slicing your two cakes into four layers. Use a serrated bread knife and cut each layer in half horizontally, try not to get hung up on accuracy here. Each layer will be beautiful in its own way.
Place the bottom cake layer onto your serving plate/stand (whatever you want to serve it on, really) and use a piping bag, sandwich bag with a corner cut (my personal set up) or simply spoon on and spread buttercream around the outer rim of the first layer. Think of it like creating a fence, so that no jam or ganache will leak out through its walls.
Now fill with half of your blackberry jam and about a third of your boozy blackberries.
Next cake layer on and repeat the buttercream fence step. Fill this layer with chocolate sour cream ganache.
Place the next cake layer on top of this and repeat again, filling with blackberry jam and another third of the boozy blackberries as we did before.
Now place the final layer on, top with remaining buttercream and spread out as desired. Top with the remaining boozy blackberries and magnolia flowers (if you can get your hands on them) and take at least 10 seconds to look at it and feel accomplished in your efforts before presenting it to anyone else. You did it!
Follow Clem’s delicious adventures on Instagram here and purchase her debut, self-published cookbook here!
Click here to download recipe printout!