In a heavy bottomed saucepan bring the heavy cream and salt to a boil. Once it begins to boil, immediately remove from the heat and pour over the chocolate chips. Let sit for 1-2 minutes.
Using a whisk stir the chocolate chips and cream until completely smooth.
Chill in the refrigerator for 2 hours until cooled but still pourable. Stir occasionally.
Once cooled, using an electric mixer, whip the chocolate ganache mixture adding 1 Tbsp of powdered sugar at a time. Sweeten to your taste and continue to beat until stiff peaks form.
Use immediately to frost a layer cake, cupcakes or sheet cake. Chill the frosted cake or cupcakes until serving.
Allow the frosted cake to come to room temperature before serving to allow the frosting to soften. (Allow to sit on the counter about 1-2 hours)
Store leftovers chilled.
Notes
Frosts 1 (9-inch) 2 layer cake or 1 (8-inch) 3 layer cake, 30 cupcakes or 1 sheet cake