I make this about every couple of weeks. My kids love this,and so does my brother, my husband, who is not crazy about BBQ even likes this dish...he can't help it, he is from up north and his family doesn't do BBQ.It has taken me a good 9 years to get him to eat a lot of our southern cuisine,lol
Combine salt,pepper,garlic and onion powers,paprika,brown sugar and poultry seasoning in small bowl. This will be the dry rub for your roast.
Make sure you kitchen sink is very clean.Wash your pork roast under cold water.While still in sink(this makes for less mess),sprinkle your dry rub all over the roast,massaging it in as you go.
Pour the 1/2 cup of water into crock pot,then place your roast into your crock pot.Let it cook on high for about 5 hours or medium for 8 hours, if you are not going to be home.
Now for the BBQ sauce,in medium sauce pan,combine your mustard,butter,apple cider vinegar,white and brown sugars and black pepper.Cook on med-low heat for about 5-10 minutes.Remove from heat and let it cool.-Note: this sauce can be adjusted to your liking,you can use more or less of the vinegar and sugars according to your tastes.
When roast is done to the point of falling apart, remove it from crock pot.Taking a fork pull meat apart and remove any bone or fat that may be left on the meat.Pour the juice from the roast into a bowl and use it to make rice or discard it.
Take 2 forks and pull all the meat apart,so it looks shredded.Place back into the crock pot and pour as much sauce as you like over the meat,mix thoroughly, cook on high for another 30 minutes.Serve with rice made from the roast drippings or on buns for an awesome BBQ sandwich.