What does fondant icing taste like ? It doesn't look like it would taste very good,but looks can be deceiving ...????

There is rolled fondant which is used to drape cakes and patissier's fondant which is flavored for candies.

It is commonly used in candy, so it always reminds me of candy confection (the inside) -- sweet and as BavarianCook says, kind of like powdered sugar. The white really doesn't have much flavor besides sweet (Boulangere - I love the idea of adding rosewater). It is really fun to work with from a decorating perspective, and the chocolate version is very chocolate, which is nice. If you don't make it yourself, make sure you buy it from a really good source -- I've been very disappointed with the stuff Wilton sells -- negative taste profile in my opinion.

It's pretty sweet, alright. I add rosewater to give it a bit of flavor, but honestly, most people don't eat more than a couple of bites of it. It's more aesthetic than anything.

Plain sweet, like powdered sugar.

It's sweet... Just like other icings.