We've covered a few methods of roasting coffee beans at home over the years using a popcorn popper, a soup can and a drill, or a hand-crank popcorn popper. To that list we're now adding a method that only needs a cast iron frying pan, a steel whisk and a colander.
Rural Spin shares the frying pan method that's been used for well over a hundred years. Simply heat up your pan on your range or grill on medium until it's somewhere between 200-260°C. Add the green coffee beans and immediately begin moving the coffee beans with your whisk. After around three minutes you'll a cracking sound similar to popcorn popping and after six minutes you'll hear a second louder crack that signifies you've reached a medium roast.
You can remove now or keep going until you reach the ten-minute mark for a dark roast. When you've reached your desired level of roast immediately move the beans to a colander and shake the colander for a minute or two to cool down the beans and separate the papery chaff.
You'll probably want to do this in small, 250g batches to ensure even roasting and keep the smoke manageable. Even with using small amounts you'll want to have fans running to get the smoke out of your kitchen -- consider doing this outside on a grill or hot plate if you have that option is available.