Chris (a software engineer) used a spreadsheet to calculate the perfect balance of mango and pineapple in his sponge. 

The cake filling was a cream, flavoured with limoncello liqueur and the topping was a mango and pineapple puree.

The sponge had no butter or butter substitutes and only used 2 eggs. Instead of fat, he packed the sponge with fruit. He said "The whole point is to make the sponge cake taste of fruit."

Judging

Paul Hollywood: "The sponge is baked to perfection."

Prue Leith: "Oh! I'll tell you what - it's full of flavour. The texture is not quite right in the middle, either because it needed a few more minutes in the oven, or because of being squashed."