Challenge: to make a volcano cake for my niece's dinosaur themed birthday party next week! My question is....red liquid icing for the lava...how do I do this? I have a pack of red ready to roll icing....can you just turn that to liquid by heating/adding hot water? Would that work? I'm based in the UK.

Thank you!

There are some very cool volcano cakes online, in general they seem to use marshmallow fluff (you can get it in Asda now) mixed with food colouring to make the lava and dry ice for the smoke.
I thought about it some time ago because I was going to make a volcano cake for a friend and in the UK could only seem to get huge quantities of dry ice. If you know someone in a theatre or somewhere that uses dry ice they might give you the very small amount you would need.
Failing that I thought of putting a little capsule (shot glass or similar) in the top of the cake and at the very last moment putting in boiling water and an ice cube (to increase the steam/bubbling) and an iridescent vitamin tab (there are Vitamin C ones in Boots and Tesco plus probably lots of other places and they come in different colours/flavours) which will fizz.

But none of that really answers your question. How are you going to get the icing to flow if it is liquid? Id probably go for piping gel to paint down the sides of the volcano possibly with some regular red icing underneath. Using royal icing would probably be easier than melting the ready to roll stuff but mixing it with water or microwaving it should make it liquidy although I have never tried either.