Fit the K-Beater bowl tool to the CHEF Titanium and add all of the cake ingredients except the cocoa powder to the mixing bowl. Combine on a low speed.
Gradually increase the speed to medium for about 3 minutes, during which time stop the machine to scrape down the side of the bowl to ensure you catch all the mixture.
Pour ¾ of the mixture into the Bundt tin. Add the cocoa powder to the remaining cake mixture in the bowl and continue to beat in until well combined.
Pour the cocoa cake mix on top in the middle of the tin. Gently drag a skewer through the two mixtures to create a delicate marble effect.
Put in the middle of the oven and bake for 50 minutes or until the skewer comes out clean and dry when you prod the cake.
Place on a cooling rack and cool in the Bundt Tin for about 10 minutes before taking it out. You may need to prise the edges of the cake away from the tin.
