Begin by softening your butter. Pop it in the microwave or soften until you can run a knife through it easily.
Zest and juice the lemons.
Now add everything into a mixing bowl. Yep, everything all at once!!
Mix well until it is very even and all combined.
Now pop around 600g of cake batter in each tin and cook for 50 minutes on 160 fan oven. It is cooked when a skewer comes out clean.
Leave to cool in the tin for 15 minutes then take out and cool fully before decorating.
Add some yellow lemon buttercream into a piping bag with no nozzle. Snip the end off and pipe blobs (technical word!!) around the outside of each layer and then just fill the middle up. Carefully add on each layer of cake without pressing down and ruining the perfect buttercream blobs. Continue until the cake is built then add some swirls and lemon slices on top. Ta-da.