Vanilla Chocolate Traybake (Tweed Squares)

Preheat oven to 170C/150CFan/340F.
In a large mixing bowl beat together the sugar and butter until pale and fluffy.
In a separate bowl sift together the flour and baking powder.
Add the egg yolks to the creamed butter and sugar mixture.
Now beat the dry ingredients into the creamed butter and sugar a little at a time, alternately with the milk until well combined.
In a clean bowl whisk the egg whites to form stiff peaks. Fold the egg whites gently into the cake mixture.
Finally grate the chocolate into the cake mixture and fold in carefully so as not to melt the chocolate as you still want "flecks" to bake into the cake.
Pour the cake batter into a tray bake pan (18x30cm/7x12") and place the tray into the hot oven for 20-25 minutes, or until a skewer comes out clean.
Remove from the oven and set aside on a wire rack to cool completely in the pan.

Place the butter, icing sugar and vanilla extract into a bowl.
Starting with the lowest setting on your electric hand blender, whisk the ingredients together. Gradually work up the settings, beating everything together, until you have a smooth buttercream icing.
Now add the milk, 1 teaspoons at a time, and continue to beat to achieve the right spreading consistency.
Spread the icing over the cake mixture and allow to cool in the fridge for 20 minutes before adding the chocolate topping.

Break up the chocolate into a glass bowl and melt with the butter over a pan of simmering water.
Stir well and once melted together, set aside to cool for 10 minutes.
Now spread the melted chocolate over the icing and again place in fridge and leave to cool. Once the chocolate has set, cut into squares and serve.

When making buttercream icing, remove the butter from the fridge an hour before hand and allow to come to room temperature. This will soften the butter and make it far easier to beat to a smooth buttercream.
Ensure the cake is cool before spreading the buttercream on top. If the cake is warm the butter will melt.
Chill the cake for at least 20 minutes before adding the chocolate topping. Also once melted, set the chocolate aside for 10 minutes, otherwise the chocolate will melt into the buttercream.

• Please note that the nutrition information provided above is approximate and meant as a guideline only •

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