- STEP 1
Heat oven to 190C/170C fan/gas mark 5. Grease a loaf tin and put a rectangle of baking parchment in the bottom. Cream the margarine and sugar together, then add eggs one at a time, then fold the flour in and add vanilla essence. Mix until smooth.
- STEP 2
Divide the mixture between two bowls. Mix milk and cocoa powder until a paste is formed. Add cocoa paste to one of the bowls, along with the grated chocolate and crush the flake bars in and mix well.
- STEP 3
Take two spoons and use them to put a dollop of each mixture in alternating each time. When you have used all the mixture tap the tin on the work surface to remove any air bubbles. Then take a skewer and gently swirl it around to create the marble effect.
- STEP 4
Bake the cake for 45 minutes or until a skewer/knife can be inserted and come out clean. Turn on to cooling rack when cooked and then serve with double cream. The cake will keep for up to 4 days and can be frozen for up to 30 days.
