First, I removed the pots from the main image using a mask selection. For once, I did this the old pen-style way, as Vertus was being annoying.
step 2 of 4
Then, I played with the warp tool (mmm warp, fun)
I kinda had the formations of those funny little reef sponges in mind...
step 3 of 4
Then I added flames using Alien Skin Fire.
step 4 of 4
Then, finally, I painted inside the pots a coal-effect, and added adjustment layers to alter the lighting. Then, I erased parts of the flames and added a couple of cloud renders for smoke.