Preheat your oven to 300°F (150°C).

Heat a large Dutch oven or heavy, oven-safe pot over medium-high heat with the vegetable oil.

Pat the short ribs dry. Season all sides with salt and black pepper.

Sear the ribs in batches until browned on all sides, about 3–4 minutes per side. Transfer browned ribs to a plate.

Reduce heat to medium. Add the sliced onion, minced garlic, and grated ginger to the pot. Sauté 3–4 minutes until the onion begins to soften and is translucent.

In a bowl, whisk together soy sauce, brown sugar, rice vinegar, sesame oil, hoisin, and Sriracha (if using). Pour this mixture into the pot and stir, scraping up any browned bits.

Return the short ribs to the pot and pour in the beef broth. Bring the liquid to a gentle simmer on the stovetop.

Cover the pot with a lid and transfer it to the preheated oven. Roast for about 3 hours, or until the meat is tender and falling off the bone.

Remove the pot from the oven and let it rest for 10 minutes. Skim off any excess fat from the surface with a spoon.

Serve the ribs over steamed rice or noodles. Spoon the sauce over the meat and garnish with sliced green onions and sesame seeds.