Preheat the oven to 180°C/160°C fan/Gas Mark 4. Grease and line 3x8” round cake tins. Place the butter and caster sugar in a freestanding mixer and beat until smooth and creamed together. 

Add the beaten eggs and Vanilla Extract and spoonful of flour, beat the mixture until all the egg is combined. 

Sieve the flour over the top of the mixture and gently fold through until just combined. 

Finally pour the raspberries into the cake mixture and gently fold through the mixture to mix through.

Divide the mixture evenly between the prepared tins and smooth. Bake for 30-35 minutes until a skewer inserted into the centre of the cake comes out clean. Leave the cakes to cool in the tin for 15 minutes then remove and leave to cool on a wire rack completely. 

Whilst the cake is baking, make the chocolate brushstrokes. Line 2 large baking trays with greaseproof paper. Break the White Chocolate into pieces and place in a microwaveable bowl. Melt the chocolate in the microwave for 30 seconds then stir, repeat heating the chocolate in 30 second bursts, stirring between each burst until the chocolate is melted.

Divide the melted chocolate between 4 small bowls. Add a few drops of Pink Food Colour Gel to one small bowl and stir through until the chocolate is pink, add a few more drops of colour if required. Repeat for the Blue, Orange and green Colour Gels, so you end up with 4 small bowls of coloured chocolate – only add a small amount of colour gel at a time to ensure the chocolate does not seize, if the chocolate thickens too much as it is coloured heat in the microwave for 5-10 seconds to loosen. 

Using a teaspoon blob a small spoonful of chocolate onto the greaseproof and using a silicone pastry brush drag the blob of chocolate in one direction to create the brushstroke effect. Repeat this for each colour until you have used up your coloured chocolate – make more chocolate brushstrokes than you need as some may break.

Place the chocolate in the fridge to set, until you are ready to use them.

Break the White Chocolate into pieces and place in a microwaveable bowl. Melt the chocolate in the microwave for 30 seconds then stir, repeat heating the chocolate in 30 second bursts, stirring between each burst until the chocolate is melted. Set aside to cool. 

Place the butter in a mixer and beat for 2 minutes until smooth and glossy. Gradually add the icing sugar making sure it is mixed through after each addition. Add the Vanilla Extract and beat the buttercream until light in texture and pale in colour. Add the cooled white chocolate and beat again. 

Once the cake has cooled, use a serrated knife to remove any domed tops from the cake. Place one cake layer onto a cake board or serving plate and cover with an even layer of buttercream. Spread a thin layer of jam over the buttercream and sandwich with the next cake layer. Repeat for the next cake layer and add the final cake layer on top. 

Spread a thin crumb coat over the top and sides of the cake and smooth out. Place the cake in the fridge for 30 minutes to allow the crumb coat to set. 

Once the crumb coat has set add a thicker coat of buttercream onto the top and sides of the cake and smooth out using a palette knife or cake scraper. 

Remove the chocolate brush strokes from the fridge and gently peel off the greaseproof paper. Place the chocolate brushstrokes around the sides and on top of the cake, you can put them in any formation you like – if the chocolate brushstrokes don’t stick to the cake or each other use a small amount of buttercream or melted chocolate to secure them in place. 

Your cake is now ready to serve and enjoy! If it is warm it is best to store the cake in the fridge to prevent the chocolate brushstrokes from melting.