Heat the oil in a dutch oven. Season the short ribs with salt, pepper, and Korean red pepper powder. Sear the short ribs until nicely browned on all sides. Remove from the pot and set aside.
Add the onion to the pot and sweat until translucent, about 4-5 minutes. Add the garlic and ginger and continue to cook until fragrant, about 1 minute more.
Add the tomato paste, and stir to remove all the tasty crusty bits. Add the beef broth until the short ribs are covered by 3/4, and bring the mixture to a simmer.
Cover the pot, and braise on the stovetop over low heat until the shortribs are very tender (replenishing the liquid as needed), about 2-3 hours. Let cool completely in the liquid.
Remove the shortribs from the liquid (I like to strain the liquid and save it for later use), and shred the meat. Add sriracha to taste, and fold in the green onions. Check the filling for seasoning, at this point too. Set aside.
To make the dumpling dough, mix the flour and salt to combine.
Slowly add water, mixing dough into a smooth mixture that comes together completely. Add more water as needed.
Cover with a damp paper towel and let sit for 15 minutes.
Divide the dough into small balls. Cover again and let sit for 15 minutes.
Roll each piece of dough into a thin circle (about an 1/8? thick). Place some filling in the center.
Dip your finger into some water, and run it around the edge of the dough. Bring the edges together in the center, and press firmly to seal.
Steam the dumpling until the center is hot and the dough is cooked, about 4-5 minutes. Serve with sweet chili or more sriacha sauce.
I always carry three kinds of hot sauce in my purse. I have a soft spot for making people their favorite dessert, especially if it's pie. My first cookbook, The Fearless Baker, is out on October 24, 2017.