Preheat your oven to 180C/160C fan and line two 8"/20cm tins with parchment paper, and leave to the side.
Beat together your butter and sugar for 3-4 minutes until light and fluffy!
Add in your self raising flour, eggs and vanilla and beat again for a a couple of minutes until smooth.
Try not to over beat - mix until it comes together and is smooth
Split the cake mix between the two tins. I weigh it to make sure its even - each mix should weigh 500g each (roughly)
Once in the tins, bake in the oven for 30-35 minutes, or until baked through. I check my cake is baked by using a skewer, and listening carefully to see if it bubbles!
Once baked, leave to cool in the tin for 10 minutes, and then transfer to a wire rack to finish cooling.
To make the buttercream, make sure your butter is at room temperature.
Beat the butter on its own for 3-4 minutes, I use the paddle attachment.
Once the butter is nice and supple, add the icing sugar in 1/2 at a time, and beat fully before adding any more in.
Add in the vanilla, and beat again for 3-4 minutes until it's all come together.
Carefully pipe or spread half of your buttercream onto the first cake, and then top with some jam.
Add the second sponge on, and then spread the rest of the buttercream on top.
Decorate with your favourite sprinkles, and enjoy!
Notes
This cake will last for 3 days at room temperature, in a cake box.
You don't have to use the vanilla, but obviously that is the theme of the cake!
You could always use vanilla beans/paste/extract over essence as its much more natural!
The jam is optional - or you can swap to whatever flavour you prefer!