Pre-heat your oven to 180°C/ 357F.
In a large bowl, combine the milk and the apple cider vinegar. Put this to the side and allow it to curdle for a couple of minutes. Then add the oil and sugar. In another bowl, sieve the flour, salt, baking powder, soda + salt and combine. Using a large spoon, add the dry mixture to the wet, whisking as you go.
Line two deep 5.5-inch baking trays with baking paper. I use silicone ones- you can buy the exact ones I use following the link in the written text above the ingredients! Pour your cake batter into both tins, evenly. Bake for 45 minutes, or until a knife comes out clean.
Once your cake is completely cool, slice the cake into four even layers. I use a cake leveller to do this as it is WAY easier than using a knife. To use this, set your leveller to the height you want your cake to be, and then use it to cut your sponges.
Melt your chocolate and then leave to cool. In a standing mixer, mix the butter until it has softened slightly (if you are working with already soft butter, skip this step). Add the icing sugar and mix on a low speed for around 30 seconds and then increase to a high speed, until combined and fluffy (around 1-2 minutes). Once your chocolate has come back down to room temperature, pour it into your mixer and beat on a low speed, until all combined. I then placed my icing in the fridge for around an hour to allow it to firm up. When i removed it, i softened it slightly by mixing it with a spoon. If you think your icing is too soft you can always add more icing sugar.
Using a cake plate, layer all of the sponges up evenly with icing. Within each icing layer, create an icing barrier around the edge and place approx 1 tablespoon of cherry jam in the middle. Piping bags make this easier.
Using the piping bag with icing in, spread the icing around the edge and the top of the cake. Use a cake spatula to smooth all out. If you don’t have these, you can do more of a rustic pattern with a knife. Place the cake in the fridge to cool for as long as possible (ideally at least a couple of hours).
Decorate the top of the cake in whatever way you want. I did icing swirls and then placed cherries on top. ENJOY!