In a small saucepan or in the microwave oven, bring the cream to a boil. Pour over the chocolate. Let stand for 1 minute, without stirring.
With a whisk, stir until the ganache is smooth. Add the butter and stir until melted. Refrigerate for about 1 hour or until the ganache is spreadable but not too stiff. If necessary, melt for a few seconds in the microwave oven.
Recipes with the "Healthy Pick" stamp have been evaluated by a registered dietitian member of the Ordre professionnel des diététistes du Québec.