Whisk the heavy cream, wine, cocoa powder, and sugar together in a small saucepan over medium heat. Once simmering, allow it to simmer for 5-6 minutes. Stir occasionally. Remove from heat, stir in the chocolate, butter, and salt. Taste. Add a pinch more salt if desired.

Allow to cool for a few minutes before using as a thin ganache. Ganache will thicken as it cools, so if you’d like to use it to frost cakes and cupcakes, stick it in the fridge for a few hours.

Cover and store leftover ganache in the refrigerator for up to 10 days. To thin out again, reheat in the microwave for 10-20 seconds.