I tried my hand at fondant last weekend, it went surprisingly well. I put a thick layer of BC under the fondant because I read that many people peel off the fondant because it's too sweet. I made homemade MMF, I thought it was yummy. I've since watched some fondant tutorials and a lot of the cakes have only a crumb coat of icing. Is either way acceptable? What do you do?

I'm no expert but I do a crump coat and then a thin coat of BC. I dont like it to be real thick because it seems to run out the bottom and can get messy.

I usually do a crumb coat, plus one more THIN layer of buttercream under fondant, just to make sure all the bumps are out, then I chill it well. If there are imperfections, they will show up once you put your fondant on, so make sure to smooth out that frosting!

Pretty much not more than a crumb coat, although I have recently started to use spackle paste as the crumb coat and then a very thin swipe of bc over that.

yep, super thin crumbcoat of buttercream, too much will make fondant bulge, bump and look uneven.

I put a coat under my fondant so people have icing to eat if they don't like the fondant. It can help smooth out imperfections in the cake.