First soak the gelatin by placing in a small bowl and just covering with cold water.
Whilst the gelatin is soaking peel and de-stone the mango. You should have about 500g of mango flesh.
Cube the mango and place in a blender with the lime juice, condensed milk and double cream. Blend until smooth.
Set aside whilst you heat up the gelatin by squeezing it to remove the excess water and placing the leaves in a small saucepan. Heat on low until the gelatin has completed melted and then stir quickly and evenly into the mango pudding.
Divide the pudding into six glasses then place in the fridge to set for at least a couple of hours or overnight.
Serve the mango puddings with a dollop of extra thick double cream on top and a grating of lime zest.