1. Sift together flour, baking powder, baking soda and salt.
2. Mix cocoa powder and coffee powder with 4 tbs warm water and make a paste.
3. In a bowl cream together oil and sugar.
4. Add in 1/2 cup of milk, vinegar, vanilla and mango puree.
5. Whisk until all the ingredients are incorporated.
6. Add the flour and with the help of a wooden spoon fold in the flour with the liquid ingredients.
7. Now divide the batter into two, keeping little more than 1/3rd for the cocoa and little less than 2/3rd for the mango flavoured batter.
8. Add the cocoa mixture to the batter and if necessary add little milk to make a loose batter. ( I added 1/4 cup to the cocoa batter and 1/4 cup to the mango batter because my batter was very thick)
9. Now grease and dust an 8" pan.
10. Drop cocoa batter randomly on the pan.
11. Fill the gaps with the mango batter.
12. Now for the next layer drop the cocoa batter on the mango batter and mango batter on the cocoa batter.
13. When finished filling the tin, with a sharp knife draw lines into the batter to get the marbled effect.
14. Preheat oven to 175C.
15. Bake the cake for 40-50 minutes. Check with a tooth pick. It should come out clean.
16. Place it on a wire rack and allow it to cool for 10 minutes in the pan.
17. Now flip the cake on rthe wire rack and allow it to cool completely.
18. Transfer to a serving plate, slice it and serve.
