I just made IMBC for the first time and we have all fell in love with it. 2 Questions though:

1. How do you smooth it? or is it only for under fondant if it needs to be smooth.

2. Is there any way to make it white, mine came out very yellow, I would love to use this for wedding cakes, but they want it white.

thanks for all your help.

Smooth with a hot knife.

Add a drop of violet gel/paste color an mix well. It'll turn white. The violet cancels out the yellow.

And yes, it works. I do it all the time because I use butter and real vanilla in my icings.

Rae

Rae is right. I do want to add that I don't like using the hot knife anymore because it makes my buttercream turn blotchy in color (even if uncolored).

Once you get it as smooth as you can with a scraper, put it in the fridge and let it get hard. Then scrape over it again and it will shave off the top layer.