Use ingredients at room temperature when making the cake. The reason for this is simple: ingredients at room temperature will combine better and make for a better bake!
When combining the wet and dry ingredients together to make the cake, make sure to only use a spatula and to fold the ingredients together. Mixing the wet and dry together too vigorously will lead to a tough, rubbery baked cake and not a lovely fluffy one.
Level the cake mixture in the tins before baking. This cake does not rise too much, and so levelling the cake mean less need to level the cakes before stacking once baked.
When making the raspberry goo, make sure to push the raspberries through a sieve before cooking the juice, to get ride of any seeds. The raspberry liquid will bubble at first and gradually thicken, reducing as it does so, into an almost jam like consistency. This will leave you with a thick red liquid that will give a rich strong raspberry flavour to the buttercream icing. Heavenly!
Make sure the cakes are completely cool before decorating. This is important to ensure the buttercream does not melt when put on the cake. I make my cakes the evening before, so they cool completely overnight before being decorated.
I like this cake as a bit of a semi naked cake. If you wanted to make enough buttercream to cover the sides of the cake too, and pipe additional decoration on top, simply double the amount of buttercream you make to give you plenty to work with.