Crush the biscuits until they are mostly crumbs, leaving a few larger pieces (about the size of a hazelnut) for texture and place in a large bowl.
Add the chopped marshmallows and cherries.
Pour in the condensed milk and mix until everything comes together, adding a little more condensed milk if you need it.
Place the mixture onto some foil or parchment paper and shape into a log. Cover the outside of the log with the coconut and roll around until it’s covered on all sides.
Wrap it up tightly in a roll and place in the refrigerator for a couple of hours. Slice and enjoy.