I tried substituting coconut milk for cream in a chocolate ganache. The result was perfectly smooth, delicious chocolate frosting that did not taste of coconut and did not taste “dairy-free.”
You barely need a recipe. Heat 4 ounces of coconut milk (I used a microwave), and pour the hot liquid over 4 ounces of finely chopped chocolate (I used Callebaut 60/40). Wait a minute, and then stir until smooth. That’s it. The frosting stays soft and shiny even two days later.
Update: I should probably add, for those people who are not used to working with ganache, that the ganache might be quite liquid at first, depending on how fluid your chocolate gets when hot, and on how warm your ganache is. As the ganache cools, it thickens. When it is thin, it can be used as a glaze, and when it is thickened, you can use it more like a frosting. The Callebaut 60/40 chocolate is less fluid when melted than some other fine chocolate and my ganache was thick almost right away. Chocolate chips are also formulated to be less fluid when melted, and also might make a ganache that is thicker more quickly. Just remember to finely chop the chocolate with a knife or in a food processor before pouring over the hot coconut milk.
One more thing: of course, this will work with heavy cream instead of coconut milk, if you want a more traditional ganache.