Works good, got this off the Internet:

Half an hour before you want to begin cooking the ribs, preheat the oven to 225 degrees F and remove the ribs from the refrigerator to warm up.
Wrap the ribs in aluminum foil. Place the ribs on a sheet pan, bone side down (meaty side up), and put them in the preheated oven. Set the timer for 3 hours.
reduce the oven temperature to 180 degrees and set the timer for 2 or 3 hours more. (The ribs are “done” at this point, but longer cooking melts away more cartilage, making them more tender.)
When the timer goes off, remove the ribs from the oven. Turn the oven to the broil setting. Remove the aluminum foil from the ribs (be careful — there will be some juices), apply a thin coating of barbecue sauce, and place the ribs under the broiler until the barbecue sauce just begins to char — perhaps 10 minutes or so. If you really like charred ribs (I sometimes do), you may want to keep the ribs in a bit longer.
OR skip the broiler part if you wish.