I am attempting to make a Thomas the Tank Engine cake which will have a battery operated train going on a track and through a tunnel made of rice krispie treats. I was thinking about putting a lake on the cake. I was going to use blue jelly for the lake. The cake will be covered with fondant.
Does anyone have any ideas or suggestions????
Thanks

Should work...or blue tinted piping gel.

Jelly is a bit too wet to put directly into fondant, it would turn the fondant into a goopy mess. Piping gel would work though. I would make the area for the lake with a couple shades of blue fondant, getting darker toward the centre of the lake, to give it the illusion of depth, then just paint a little clear piping gel over the blue (or you could tint the piping gel slightly).