FRY the onion in hot butter, you can do it directly in the press cooker, when onion turns transparent take away from heat and let it cool. PUT in the cooker raw beans with enoug water, once butter has been fried. You must cover the beans and overflow for the double. Close the pot and cook for 45 minutes. LET it cool so you can open it. Once opened add beans to the meat, if you see they are too dry, you can add water but it must be hot. Cover the pot again and let it cook for 40 more minutes. TURN OFF and when you can, open it, season with salt and you must cook for 10 more minutes with the pot, open. SERVE beans and pork in individual bowls, with radish, a pinch of orégano, “chiles habaneros” and chopped cilantro. *Some people like it with lemon juice.