Brown seasoned short ribs in batches, 12–14 minutes per batch. Set aside.
Sauté scallion whites, garlic, and ginger. Add spices. Deglaze with wine.
Return beef to pot. Add soy sauce and water. Simmer 1½ hours.
Caramelize onions in butter until golden, about 45 minutes.
Shred beef. Strain broth and discard solids.
Combine beef, broth, and onions. Simmer 30 minutes. Stir in vinegar.
Cook noodles. Divide among bowls. Ladle soup over and top with scallion greens.