Adapted from Marcels Desaulniers
2 cups packed brown sugar
2 cups heavy cream
8 ounces semi-sweet chocolate, chopped
6 tablespoons butter cut into 1-tablespoon pieces
Bring all ingredients to a boil in a medium saucepan, stirring to dissolve the sugar and melt the chocolate and butter. Simmer for 25 minutes, stirring frequently, until thickened and smooth. Pour into baking sheet with sides. Refrigerate 2 hours.
When chilled, scrape frosting into stand mixer bowl with paddle attachment. Whip for about 2 minutes, till lighter in color and slightly fluffy. Use to ice cake or cupcakes...keep refrigerated for best results.