The buttercream centers that I have made in the past are from the "Antoinette Pope School Candy Book" dated 1949. If they are the same "buttercreams" that you are tasting, they are basically a fondant recipe that has a small amount of butter added after the sugar syrup has cooled on the marble...then you work it like fondant till it is cool and thick. Some people really like them but I think that they are too sweet. I hope this helps.... While I am here, I want to take this opportunity to let all of you know how impressed I am with your breadth of knowledge and supportive nature. Marshmallows brought me here and I haven't left. Thank you , Amelia