i'm sure the longer you cook them, the better they turn out, but it was late and i was craving rice and bean burritos with refried beans and i only had canned whole pintos haha. i just used olive oil and mashed them up, reserved some of their juices and added a little watter just to thin it out a bit. they went through this weird magical transformation (seriously, they went from brown to white then back to brown again), but tasted super good. between this and homemade tortillas using olive oil, i'm a firm believer that it brings something to the table when it comes to mexican food. then again, i love olives and just about anything affiliated so i'm biased.