Place white chocolate in a small, heat-proof bowl and heat for 30 seconds. Stir very well, then return to microwave and heat in 15-second increments, stirring very well in between, until chocolate is completely smooth and melted.

Set chocolate aside to cool for at least 15 minutes and no longer warm to the touch (otherwise it will melt the butter and you’ll have a greasy mess).

While chocolate is cooling, place softened butter in the bowl of a stand mixer (or you may use a large bowl and an electric hand mixer) and beat until creamy and well-whipped.

With mixer on low-speed, gradually add melted, cooled chocolate and stir well.

Gradually add powdered sugar, scraping down the sides and bottom of the bowl periodically to ensure that all ingredients are well combined.

Sprinkle in salt and vanilla extract and stir well.

With mixer on low-speed, gradually add heavy cream to frosting. Gradually increase speed to high and beat for 30-60 seconds or until desired consistency is reached (should be light, creamy, fluffy, and slightly increased in volume). If you beat too much air into the icing and would like a smoother frosting, use a spatula to cut through the batter and work out any air bubbles.

Pipe or spread frosting onto prepared, cooled baked goods.