I want to do a retirement breakfast at work, and a I want to use the boil in the bag omelet method. How do you keep water boiling without a stove? a sterno, crockpot, or chafing dish? Has anyone done this? How do caterers do portable omelet parties?

I suppose that such methods leave out of the question fluffy omelets. I wonder, though, if somebody knows how to make fluffy omelet in a ziploc bag, as that would really be a surprise for all my colleagues.