As a couple others already stated... timing is everything. I do this exact same thing all the time! One of my favorite meals is ribs slow cooked in BBQ sauce, then to throw them on the grill for a little bit to make the outside "crunchy".
Here is what I do:
- Place ribs in slow cooker. (Usually I do spare ribs, but full racks cut in half work).
- Mix in a bowl your favorite BBQ sauce with water to make it a little thinner. (I know a true cook would make their own sauce, but with all the different BBQ sauces available on the store shelves these days I figure whats the point). Personally I use Stubbs BBQ sauce which is from a Texas restaurant but the sauce is available here in Michigan Grocery stores.
- Cook on low or high. If on low figure on checking the consistency in about 5 hours. If too tough go for another hour and check again. Repeat with discernment. If doing it on high be careful... probably need to check at 2 hours for the consistency then again at 30 minute increments.
- Once they are almost falling off the bone but still in tact, you know your at the right point to pull them out of the crock pot. Place them on a pre-warmed grill and grill to the desired brownness or crunchiness. I also brush on more BBQ sauce on both sides, and brush yet more on the top side when I serve them.
This is the poor mans way of doing ribs. The right way of course is to do them over a slow heat like in a smoker. You can do this with a regular grill... I have done it before, but it takes time and a watchful eye. I would have to plan on being home all darn day to do it. You can even put wood in there to give it a smokey flavor. The process is that you use only one burner on low and put the mean on the "cold" side of the grill (not over the one burner that is on). With charcoal, you keep the charcoal on one side and the meat on the other. You can even put a pan of water over the hot side to give off some moisture at the beginning. This will give the ribs that classic crunchy outside with the tender inside. Especially if you put a rub on the meat.
Here is more how to do that: http://amazingribs.com/recipes/porknography/best_BBQ_ribs_ever.html
Ive done that once and it was insanely delicious! As the article said its 3 hours or more... i found it took 8 hours on the grill with this method. (I have a gas grill).
Just thinking about this is making me want to do this again though!
Cheers!