I watched an episode of Ace of cakes and Duff used modelling chocolate under his fondant. He said it gave a sharper edge to a square cake. Has anyone done this??? What kind of modelling chocolate do you use???
You can buy it from several on line stores, or make it yourself. It is a bit like tootsie rolls, even the white, in texture.
there are recipes in the recipe section, it might be called candy clay.
It does make the cake heavier.