Frosting: Allow the ganache to sit at room temperature for 2 hours, until thick and spreadable and use to fill and/or frost cakes.
Whipped ganache: To make a whipped frosting for cupcakes, allow to ganache to cool to room temperature for 2 hours. Then place it in a large mixing bowl or stand mixer and whisk with an electric mixer for 5 minutes, until light and fluffy.
Store in a bowl covered tightly in plastic wrap or in an airtight container and refrigerate. It will keep in the fridge for up to 2 weeks. You can freeze it once covered airtight for up to 3 months. Allow it to defrost in the fridge overnight before using.
Refrigerate the tins of coconut milk overnight, then only use the thick cream from the top of the can. Depending on the brand, you will need 1-2 400ml cans, I find Biona and Nature's Charm have the best yield of coconut cream.
If using plant-based cream, it needs to be double cream and not single cream. I use a brand called Emlea.