Preheat your oven to 375℉. Place the ginger, lemongrass, cinnamon sticks and star anise on a baking tray. Bake for 15 minutes. Generously season the short ribs with salt and pepper.
Once the baking time has passed, remove the tray and reduce the oven heat to 325℉. Place a dutch oven (or other large oven safe pot) with olive oil over medium-high heat.
Add the garlic, lemongrass, ginger, cinnamon sticks and star anise. Allow this to cook for about 5 minutes. Cook each of the short ribs until all the sides are browned.
Mix the soy sauce, hoisin, rice wine, brown sugar, gochujang, and beef broth together. Pour them into the pot.
Add the meat and bring to a slight boil. Place the dutch oven (covered) in the oven and cook for 3-4 hours or until the meat is tender.
Thirty minutes before the beef is finished cooking, place a pan over medium-high heat. Add the diced bell peppers and onions. Cook until softened, about 10 minutes. Set aside.
After the meat is done cooking, it is time to prepare the filling. Take the beef and shred it in a bowl.
Add the scallions, bell pepper, and onions. Mix until well combined. Feel free to add some of the sauce the meat was cooking in. Make sure to not add too much because it will make the filling too wet and that make the dough soggy. Season with salt and pepper.