Start by taking the gelatin in a sauce pan, cover with water and let it sit for 5 mins. Now heta this gently till it is melted. Set aside.
Now take the tender coconut and the coconut water in a blender and puree till smooth. Set aside.
Take condensed milk, milk, sugar in a pan, heat till it comes to a boil. Now remove it from heat and add in the tender coconut mix, chopped tender coconut, vanilla and gelatin mix. Mix well.
Pour this in a greased mould and let it set for few hours.