Start by making the biscuit base. Mix together the crushed biscuits, toasted shredded coconut and melted butter and press into the base and sides of a 22cm spring form cake tin. Place in the fridge to harden. Meanwhile, place the gelatin sheets in cold water to soften, discard the water and melt the gelatin. Next, blitz the mango to a fine puree with the icing sugar. Whip the double cream and vanilla to almost soft peaks. Add in the cream cheese and 2/3 of the mango puree and whisk through. Finally, whisk in the liquid gelatin to a smooth mousse. Spoon the mixture into the biscuit base and allow to set in the fridge for 2-3 hours or overnight. When ready to serve, spoon over the reserved mango puree and sprinkle over the toasted coconut flakes.