Preheat the oven to 180ºc/160ºfan and line three 20cm/8inch round cake tins with baking parchment – leave to the side.
In a stand mixer, beat together the unsalted butter and light brown soft sugar for a few minutes until light and fluffy.
Add in the self-raising flour, eggs, baking powder (if using) and vanilla and beat again briefly until combined.
Divide the mixture between the three tins and smooth it over – bake for 25-30minutes until the cakes are golden and when the cake springs back (skewer should also come out clean)!
Once baked, leave the cakes to cool in their tins for 10 minutes or so, and then remove and leave to cool fully on a wire rack.
For The Decoration
Beat the room temperature unsalted butter with an electric mixer for a couple of minutes to loosen it
Gradually add the icing sugar on a slow speed until it is combined then speed the mixer up and mix for 3-4 minutes until thoroughly combined and smooth.
Add in the biscoff spread to the buttercream and continue mixing, and gradually add the boiling water until you reach the desired texture if it is needed! Keep on beating for 5 minutes until whipped and silky smooth!
Using your favourite piping tip, I used a large round tip, pipe the buttercream onto the bottom layer of the cake. Add the second layer, and pipe buttercream on again!
Add on the third layer of the cake and pipe on the rest of the buttercream.
Drizzle over some melted biscoff spread, and add on some biscuits, crushed biscuits and some sprinkles. Alternatively you can just slather the buttercream on instead! Enjoy!
Notes
I love this style of cake as you can tell from the few I have made, and I happen to have 3 8″ tins, if you don’t have 3 tins you can make a smaller version of the cake with two 8" tins (Can take slightly longer to bake)
300g Butter
300g Sugar
300g Flour
6 Medium Eggs
1.5tsps Baking Powder/1tsp Vanilla
2/3 of the decoration recipes!
You can buy the Biscoff/Lotus spread in nearly all supermarkets in the UK now, its usually found next to Nutella!
I wouldn't add the water to the buttercream unless it is essential. Often on a sunny or warm day, it won't be needed!
This cake will last in an airtight container for 3 days, at room temperature.