A pressure cooker works best, but you can use a large pan instead. I have a large pressure cooker that I use for these, but I don't actually pressure cook them, the actual cooker just seems to work best while cooking them.
Here's what you need:
6 cans green beans drained (I actually use the cheap ones from Sav-a-Lot Grocery)
1 small onion sliced thin
4 tbsp bacon grease (there is no substitute!) I always save mine after cooking bacon and store it in the fridge until I need it.
salt/pepper
Preheat the pan until it's really hot, then add the bacon grease, once it's melted add the onions. Then throw in the green beans one can at a time, salt and peppering as each can is added. Once you have them all added stir it up well so that all the green beans get a little of the bacon grease coating. The trick to great southern green beans is to cook them at least 30 minutes, stirring every 5 minutes or so and not having the liquid from the can to water them down. After you have cooked them 30 minutes, cover and let them set for 15 minutes, that's the other trick! They have to rest, don't know why, but grandma always rested her green beans! I'm proud to have learned her secret before she passed on!
They are great reheated in the microwave, which is why I fix such a large batch at once, we have them with two or 3 meals and that way I don't have to cook them every day!
Enjoy!