I prepared my buttercream from from a recipe I found here on CC. The recipe called for milk, and butter. I've iced the cake and left it on the counter. Now am I going to make people sick? Does this type of icing need to be refrigerated or is it ok to leave out now that it's all mixed up with the sugar?

You should be able to leave it on the counter. There is enough powdered sugar in it to keep it stablized. My buttercreams stays out for days and it is fine.

You should be able to leave it on the counter. There is enough powdered sugar in it to keep it stablized. My buttercreams stays out for days and it is fine.

You should be able to leave it on the counter. There is enough powdered sugar in it to keep it stablized. My buttercreams stays out for days and it is fine.