Buttercream Frosting

½ cup unsalted butter at room temperature
3 cups confectioners sugar
1 teaspoon pure vanilla extract
½ cup heavy cream, cold

In a large bowl or stand mixer fitted with paddle attachment, cream together softened butter and shortening until fluffy and well combined. Add the powdered sugar, vanilla extract, and salt. Mix until well blended. At this point, the frosting will be very stiff. Slowly mix the heavy cream at low speed. Once it is fully mixed in, increase the speed to high and beat for 5 minutes, scraping down the bowl occasionally.