• Preheat your oven to 180 degrees celsius (fan-forced) and line the base of a loaf tin with baking paper before lightly greasing the sides.
• Place the butter and caster sugar into the bowl of an electric mixer (or use handheld beaters) and beat for 3 - 4 minutes or until pale and creamy.
• Add the vanilla extract and milk and mix to combine.
• With the mixer running on a slow speed, add the eggs one at time and beat well.
• Add the self raising flour and mix until just combined.
• Transfer the mixture in three equal parts and add the cocoa to one and a couple of drops of pink food colouring to the other. Mix to create the coloured mixture.
• Add spoonfuls of the three different coloured mixtures to your prepared loaf tin and once all the mixture is in the tin, use a butter knife to gently swirl the mixture to create the 'marble' effect.
• Place the cake tin into the oven and cook for 30 - 35 minutes or until your marble cake is cooked through when tested with a skewer.

Thermomix Instructions

• Preheat your oven to 180 degrees celsius (fan-forced) and line a 20cm round cake tin with baking paper.
• Place the butter (softened) and caster sugar into your Thermomix bowl and mix for 30 seconds on speed 3.
• Scrape down the sides of the bowl and mix for a further 20 seconds, speed 3.
• Add the vanilla extract, milk, eggs and self raising flour and mix for 10 seconds, speed 4. Scrape down the sides of the bowl and mix for a further 5 seconds, speed 4 or until well combined.
• Follow instructions from step 6.