I recommend cutting the rack in half or into thirds to make moving from pan to plate when cooked easier. You may also remove the membrane if desired.
Season ribs with desired dry rub. At this point you can allow ribs to sit overnight for the rub to be absorbed better, however this isn't necessary.
Preheat oven to 250 degrees.
Use a deep pan with a cooking rack in it and pour water into pan. Do not allow water to reach the rack.
Put ribs on the rack so they sit above the water.
Cover the pan with two layers of aluminum foil and make a tight seal around the edges.
Put the pan in the oven and cook for 6 to 8 hours for ribs that will fall apart and need to be eaten with a fork. Cook 4 to 5 hours for ribs that will be very tender but remain on the bone.
When done cooking for desired length of time remove from oven and remove foil. CAREFUL the pan will have lots of very hot steam built up and it can easily burn you. I recommend using tongs to pull the foil back.
Turn your broiler on to high and have your oven rack in the upper half of the oven.
Leave ribs in the pan and brush with your favorite barbeque sauce.
Place the pan of ribs under the broiler and broil until the sauce starts to caramelize. Keep an eye on it to make sure it doesn't burn.
When the sauce has fully caramelized remove from the oven and serve.