Is it possible to use swiss merinque buttercream for the crumcoat when covering a cake in fondant? I made this buttercream for the first time yesterday in baking class (using white chocolate to help stabalize it), I thought it turned out delicious and thought about using it on my cakes. Has anyone used it and how did it turn out?

It works great under fondant. Just make sure you chill the cake until the icing is very firm before adding the fondant.

It is great, just like the previous post said , make sure it's well chilled first. This icing does not "crust over".

Thanks! Since it doesnt crust, will the buttercream start melting, or falling as the kick sits out? I have a long deliver also, so it will be sitting out for a few hours.

I use SMBC exclusively. Unless the room is really warm, no it won't melt. It holds up great and is a dream to put fondant on when it's cold.