Spray the slow cooker with non-stick cooking spray (or use a slow cooker liner to make clean up a breeze!).
Take your slab of ribs (make sure that they are defrosted) and cut into individual slabs (about 2-3 ribs each). Throw the ribs into the slow cooker.
Mix 3 ¼ cups pineapple juice and the brown sugar together and pour over the ribs.
Cook on HIGH heat in the slow cooker for 7-8 hours or LOW for 10-12 hours.
After they are done in the slow cooker, use tongs to gently pull them out (they will literally fall apart when you touch them).
Turn the grill on medium heat. While the grill is warming up, mix together the bottle of BBQ sauce and ¼ cup of pineapple juice you saved from earlier.
Place the ribs gently on the grill and and brush with BBQ sauce.
Turn the ribs twice, slathering with more sauce each time (you can't have enough sauce).
They will take about 10-15 minutes to glaze over (as soon as that sauce starts to turn sticky, you know they are done).
Serve immediately and enjoy.
Notes
This marinade works for chicken, beef, and other pork cuts, but cooking time and nutritional information will vary.Recipe slightly adapted from Domestication in Progress.