Whipped Chocolate Buttercream Frosting

I really liked this frosting and this is coming from a non-buttercream-loving girl.  It probably has something to do with the two sticks of butter and melted chocolate chips.  So not the least expensive frosting in the world, but definitely tasty, so I'm going to keep it here for reference.  A key to a good buttercream frosting is to let the butter come to room temperature but not to microwave it.  And then whip it good!  It does get hard in the fridge, so it's better to bring it out in advance before serving so it has a chance to soften up again.


WHIPPED CHOCOLATE BUTTERCREAM FROSTING
(found here)

Ingredients
1 cup butter (2 sticks), softened, room temperature
½ tablespoon heavy whipping cream (I used milk this time because I didn't have any)
1 teaspoon real vanilla extract
½ cup semi-sweet chocolate chips, melted and cooled
½ cup unsweetened cocoa powder, sifted
2½ cups powdered sugar, sifted (spoon into measuring cup to measure)
pinch of salt

Instructions
In a large bowl cream butter until fluffy.
Add in heavy cream and mix until light and fluffy.
Mix in vanilla extract.
Mix in melted chocolate chips.
Mix in cocoa powder and powdered sugar until frosting is light, fluffy and whipped.
Stir in salt.
Frost cake or cupcakes.
Store leftover frosting in a covered container in the refrigerator. Let come to room temperature before using.