ube cake is basically a chiffon cake with violet food coloring in it. use the powdered food color, as the liquid unstabilize the cake mixture. then make about 3 cakes. fill the cake with a filling of your choice. then coat the stacked cakes with softened ube ice cream. then put in a blender the 3rd cake and make into a crumb, which you then cover the cake up. thus, ube cake have that felty look from the crumbs. voila! ube cake! i think at first ube cake was made from real ube, but i think it made it heavy so they just omitted the ube from the cake and use food coloring instead.