For the sauce: Stir together all sauce ingredients in a small saucepan and bring to a boil; reduce heat and simmer, covered, for 30 minutes.
For the pork: Stir together spices in medium bowl; add pork and toss until coated. Heat 1 Tbsp. oil in a stock pot. Add pork and cook until browned on all sides. Remove from pot. Heat remaining oil and add onion; cook and stir over medium-high heat for 5 minutes to brown. Add pork back to pot with mango and 1 ½ cups mango barbecue sauce (reserve extra sauce for serving); cover and cook over low heat for 2 ½ hours or until meat shreds easily with a fork.
Serve pork on rolls with a drizzle of barbecue sauce.