To melt the chocolate, find a heatproof bowl that fits snuggly into the top of a small saucepan. Break up the chocolate and place the pieces (or buttonin the bowl.
Fill 1/3 of the saucepan with water and then set the bowl on top again. Check that the water isn't touching the bottom of the bowl and if it is, tip some out.
Remove the bowl again and bring the water to the boil. Once boiling turn down the heat to medium/low or to where the water is simmering.
Place the bowl of chocolate back on the saucepan and stir often (especially the sides and bottom so it doesn't stick and burn), until all of the chocolate has melted.
Leave the chocolate in the bowl, remove it from on top of the saucepan and place it aside.
Place the desiccated coconut and milk into a small bowl. Mix the two together and leave aside.
In a medium-sized bowl using an electric beater, on medium speed, beat the cream for around 2 ½ minutes or until stiff peaks form. Place it aside.
Place the cream cheese and the castor sugar into a large bowl and using the electric beater again, still on medium speed, beat it together for around 3 minutes or until it's smooth and light 'n' creamy.
Scrape the bowl down and add the coconut and milk mixture, mixing it in until it's well combined.
Add 2 tablespoons of the mixture to the melted chocolate and fold it through.
Add the chocolate to the cream cheese mixture and still on medium speed, beat in it until it's nicely combined.
Place 1/3 cup of cold water into a small heatproof bowl and sprinkle the gelatine over the surface.
Boil the jug (kettle).
Find another heatproof bowl that is larger than the small bowl containing the water and gelatine and place the smaller bowl inside it.
Carefully pour some boiling water into the larger bowl so that it reaches the same height as the water and the gelatine inside the smaller bowl (being careful not to get any water inside the small bowl).
Mix the water and gelatine together until all of the gelatine has dissolved.
Scrape every little bit of the dissolved gelatine and water into the bowl with the rest, and on a lower speed, beat it in for around 1 minute or until it's nicely blended. Scrape down the bowl.
Add the whipped cream and using a large spoon or spatula, fold the whipped cream through the cream cheese mixture until well combined.
Spoon the filling into the tin and roughly smooth the top over with a metal spatula or the back of a dessert spoon.