I carry a small propane stove in my truck, so I don't have to use my trusty shovel. The trick is to sterilize the shovel by getting it red hot, being careful not to set the handle alight. Many a sausage was cooked like this in the railways. Bloody good too.
I once ended up in the Coromandel on a very impromptu holiday, with a fine bunch of ladies. I was able to appear very manly, by steaming some mussels I foraged in the hubcaps of my car, using a pair of vicegrips as a handle.