Blend, pear, apple and water until smooth then combine with soy sauce, brown sugar, sesame oil, mirin, garlic paste, kosher salt and pepper in a bowl. Add ribs to a large zip-top bag or container, pour marinade over them, and chill overnight or at least 2 hours.
Transfer ribs and marinade to the slow cooker. Add 1/4 cup water or broth if needed.
Cook on LOW for 7–8 hours or HIGH for 4–5 hours, until ribs are tender.
Place ribs on a foil-lined baking sheet, lather with japanese bbq sauce and broil for 2–3 minutes per side for a sticky, caramelized glaze.
Serve ribs over a nest of garlic noodles. Top with scallions and sesame seeds.