For the short ribs: Place an oven rack in the lower third of the oven. Preheat the oven to 350 degrees F. Sprinkle the ribs all over with 1 teaspoon salt and 3/4 teaspoon pepper. In a large heavy-bottomed Dutch oven or ovenproof stock pot, heat the oil over medium-high heat. Add the ribs in batches and brown on all sides, 7 to 8 minutes. Remove the ribs and set aside. Add the garlic, onions and remaining salt and pepper and cook, stirring frequently, for 2 minutes. Add the wine and mustard and bring to a boil, scraping the brown bits stuck to the bottom of the pan with a wooden spoon. Return the ribs to the pot and pour over the beef broth. Cover and transfer to the oven until the meat is fork-tender and falls easily from the bone, 2 hours 30 minutes.
For the glaze: Heat the oil in a small saucepan over medium heat. Add the ginger and garlic and cook, stirring, until fragrant, about 2 minutes. Add the soy sauce, brown sugar and red pepper flakes and bring to a boil. Reduce the heat and cook until thickened slightly, 5 minutes. Cool to room temperature.
For the corn puree: In a medium skillet, heat the oil over medium heat. Add the onions, salt and pepper and cook until softened, stirring occasionally, about 5 minutes. Remove from the heat and cool slightly. Transfer to a food processor with the corn and pulse until combined. Add the cream and process until smooth. Set aside.
For assembling and cooking the dumplings: Pull the short rib meat from the bone and shred into a bowl. Lay the wonton wrappers out on a cutting board. Place 1 tablespoon of the corn puree on each wrapper and top with 1 tablespoon of the shredded short ribs. Moisten the edges of the wonton with water. Lift the corners of the wrapper and pinch them together. Continue with the remaining dumplings.
Heat 1 tablespoon vegetable oil in a large nonstick skillet over medium-high heat. Place half of the dumplings flat-side down in the oil and fry until the bottoms are golden brown, 2 minutes. Add 1/4 cup water, cover the skillet and steam the dumplings until the wontons are cooked through, about 5 minutes. Transfer to a baking sheet and tent with aluminum foil to keep warm while you cook the rest of the dumplings. Transfer all the dumplings to a platter and serve with the soy chili glaze.