Secret Ingredient Chocolate Cake Recipe

Secret Ingredient Chocolate Cake

This cake, would you believe it, has mashed potato in it! It keeps it moist - but don’t worry, you won’t be able to tell. Amaze your family by telling them afterwards, they won’t believe it!!



TIME: 40 mins

TEMPERATURE: 180C (gas mark 4)


1. Defrost mash in the fridge the night before.

2. Preheat oven to 180C.

3. Pop a heatproof bowl over a pan of boiled water. Don’t let the bowl touch the water. Melt broken up bar of chocolate in bowl. Add condensed milk, butter, sugar. Mix gently whilst it’s melting.

4. Remove from heat and let cool a little.

5. Sift flour and baking powder into a bowl,add the mash to bowl and pour in chocolate mixture. Beat the egg and add that too. Mix well.

6. Grease and line x2 20cm loose bottom sandwich cake tins with greaseproof paper.

7. Add mixture to tins, dividing equally.

8. Bake for 30 mins. Meanwhile, make the icing. Melt chocolate, condensed milk and butter as above. Leave to cool.

9. Allow the cakes to cool slightly in their tins then remove from tins and allow to fully cool. Sandwich the cakes together with the icing. And top with some too -smother all over the sides. Decorate with white chocolate buttons.

HACKS: Keep an eye on your chocolate whilst it melts to see it doesn’t curdle. Especially be careful that the bowl doesn’t touch the hot water as this will also curdle the mixture.


150g dark chocolate

100g condensed milk

100g sugar

1/4 900g bag of DEFROSTED mashed potato

200g self-raising flour.

1 level teaspoon baking powder (don’t worry if you don’t have any, it’ll still work)

1 large egg

Milk chocolate icing:

150g milk chocolate

150g condensed milk

20g block butter

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