Heat a skillet or slow cooker to high and add oil.
Season pork roast with salt and pepper. Add to hot skillet or slow cooker and brown on each side.
Meanwhile, slice peaches in half, remove pits and brush with a bit of olive oil. Grill until charred on the skinless side. Remove from the grill set aside until cool enough to handle. Slip off the skins and coarsely chop.
Remove pork roast from heat and set aside.
Add remaining ingredients, including prepared peaches, to slow cooker (along with hot oil from skillet, if using).
Set slow cooker to medium and cook for 5 – 6 hours, until pork is tender.
Remove pork from slow cooker and set aside. Blend barbecue sauce with stick blender.
Shred pork roast and mix with about one cup of the barbecue sauce.
Save remaining sauce for another use. It will keep in the refrigerator for a week or so.