Moist and flavorful, classic vanilla cake paired with raspberry buttercream frosting and homemade raspberry jam. A perrfect combination of sweet and tangy!
Preheat your fan oven to 160°C (325°F) or 175°C (350°F) if you're not using a fan oven. Grease and line with parchment paper three 6-inch (15-cm) round cake tins. Alternatively, you can use two 8-inch (20-cm) cake tins.
In a medium bowl sift together flour, baking powder and salt. Whisk until combined and set aside.
In a measuring jug combine sour cream, whole milk and vanilla extract. These are your wet ingredients.
In a bowl of a stand mixer fitted with a paddle attachment, cream the butter and sugar on a medium-high speed until pale and fluffy. (approx. 3 min) Stop the mixer and scrape down the bowl.
Turn the mixer to medium-low speed and add eggs one at a time – making sure it’s fully incorporated after each addition. Stop the mixer and scrape down the bowl.
Add your dry and wet ingredients, alternating between one another, starting and finishing with dry ones. (3 additions of dry and 2 of wet ingredients)
Divide the batter evenly among the 3 tins and bake for 20-25 minutes or until skewer inserted in the middle comes out with few moist crumbs. Do not overbake it.
Once they're done, let the cakes cool for 10-15 minutes on a wire rack before removing them from the pans to cool completely. They will continue to cook in the pan, so it's important that the skewer is not entirely clean. Otherwise, your cake will overbake and that will cause dryness.
For the Raspberry Jam
Cook frozen raspberries with sugar over a medium-high heat until it reaches boiling. Turn the heat down and let it simmer for approx. 15 minutes or until it thickens. It's better to be thicker than looser, the plan is to lose a lot of water content and have concentrated flavour.
Strain the jam through a sieve to get rid of raspberry seeds and make it smooth and beautiful. Cover it with cling film and leave it to cool in the fridge.
Raspberry Buttercream
In a small saucepan (I always use heavy-bottomed one to prevent burning) combine flour, sugar, salt and milk. Cook over medium-high heat, stirring constantly with a whisk until it thickens. This can take about 15 minutes. The moment you realize it's thicker, cook for another 3-4 minutes.
Once it's done, strain it through a sieve into a plate, put a cling film over it touching the surface to prevent "skin" forming and let it cool to room temperature. This is your pudding base. You can do this in a fridge, but before using it let it come to room temperature.
Using a stand mixer fitted with the paddle attachment, beat the butter for 5 minutes until it's pale and fluffy. Then add spoonful by spoonful of previously made pudding. Mix until it's all nicely incorporated and with no lumps. Add vanilla extract with berry jam and mix until everything is combined. Be careful not to add too much jam, otherwise your buttercream might curdle.
Note: If you want to decorate a cake in an ombre effect, before adding raspberry jam, take out some of vanilla buttercream and leave it aside for decorating.
Assembly
Using a cake leveler or a long serrated knife level the tops of your cakes if needed.
In the middle of your cake board or a serving plate put some buttercream to stop the cake from moving around.
Place one cake layer on a cake board or a serving plate. Using a small offset palette knife or a piping bag, spread the frosting over the cake and drizzle some berry jam over the frosting. Top it with the next cake layer and repeat the process.
Place final layer on top, upside down, and do a thin crumb coat on the cake. Chill for 20-30 minutes in the fridge before final decorating.
Once cooled, frost and smooth the top and sides of the cake with remaining frosting. Divide the raspberry one in two so you can add some burgundy gel food colouring into one and get a darker shade. Including the vanilla buttercream you separated before adding raspberry jam, you should have three colours in front of you.
Using a small offset palette knife or a piping bag, place the frosting all over the cake, creating three ombre stripes. Smooth and even everything out using a cake scraper, then use the back of a small or a big offset palette knife to create a rustic swirling effect.
Pile up some raspberries and your cake is ready! :)
Notes
If you don't have a stand mixer, you can use a hand mixer.
Not all ovens are the same. I suggest checking the cakes at 18 min mark and then adjust the baking time accordingly. Get to know your oven!
If you still don't own one, I advise you to buy a kitchen scale - they're cheap and easy to use, and always guarantee the same results in baking!
The cake is best eaten at room temperature. You can keep it in a fridge, wrapped in cling film, but take it out of it at least half an hour before serving.