TLS is translucent liquid sculpey - a liquid polymer. im not sure what you could use as a alternative, but dont worry, i didnt use any TLS the first two times i made this, and they looked nearly the same, but i suppose the TLS would help it keep its shape, and i noticed that when i dont use TLS, after cooking there was gaps and holes in the layers of cake, so the TLS must keep the layers together. hope that helped xD