You can go to Ice Mountain, and kill an Icefiend. (use the combat bracelet teleport to the Monastery, use the Edgeville home Teleport, or use the minecarts to get there quickly) Icefiends do not drop ice gloves, but they can cool your rock cake with their breath after you kill them.
If you don't have the Mining level to get to the Ice Queen, or the inclination to kill an icefiend on Ice Mountain, you can simply leave your rock cake in your bank for around 4 hours and it will have cooled down on its own.
Multiple cakes can be acquired after the quest by paying Rohak 100 coins for each one. The ingredients are not required again, though the cake WILL need to be cooled down again after completion of the quest.