Preheat oven to 350 degrees F.
Puree pineapple in food processor or blender until smooth. Set aside.
Heat 1 tbsp oil in large dutch oven over medium high heat. Brown short ribs, about 2 minutes on each side. Remove from pot and set aside.
Add remaining oil to dutch oven and cook chopped onion until soft, about 5 minutes. Add pureed pineapple, pineapple juice, chipotle peppers in adobo sauce, stock, salt and pepper. Bring to a boil.
Once boiling, return short ribs to dutch oven. Cover and place in oven for 2 - 2 ½ hours, or until short ribs are fork tender.
Remove from oven and shred.
Serve in slider buns topped with slaw.