Place ribs in slow cooker and cover with BBQ sauce. Cook on low for 8 hours (or 4 hours on high). Remove from slow cooker and shred, return to slow cooker and keep warm until ready to serve. About an hour before serving bake potatoes (see link above for baking method).
Take baked potatoes and cut an oval hole, lengthwise, from the top. Scoop out the potato, leaving a small amount of potato around the edges (you don't want to scoop out too much and rip a hole in the skin).
Place the potato "scoopings" into a medium-sized bowl and add butter, ranch dressing, sour cream, salt, pepper, chives, and cheese.
Mash together with a fork until well mixed. Place mashed potatoes evenly back into the potato skins and make a depression in the top with the back of a spoon (the potatoes may seem overflowing.. you can remove a little of the filling if needed).
Spoon a large scoop of shredded beef into the top of the potato and top with extra shredded cheese.
Place back in 350-degree oven for about 15 mintues or until potatoes are hot all the way through.