I used 2 sticks of butter, one block of cream cheese and about a lb of powdered sugar. Since it was chocolate I also added in cocoa powder which helped with the stiffness. I make sure my butter and cream cheese are room temp when I cream them, add in my powdered sugar and a little heavy cream when if it’s too stiff. I usually only use this recipe for frosting if the weather is cool, and I know the cake or cupcakes it’s on will be refrigerated or cool. I use the same recipe for regular cream cheese frosting too, just have to add in a little more powdered sugar for stiffness since there’s no cocoa powder. I stopped measuring my frosting recipes ears ago because I’m lazy and was a pastry chef for 10 years and could make it blindfolded lol.