Season the short ribs with salt and pepper then coat in 3 tablespoons all-purpose flour. Set aside.
In a heavy skillet or pot, or if your slow cooker has the sear option heat to medium-high. Add oil, and brown the short ribs in batches on both sides. Place on a plate until they are all done then put them in the slow cooker..
In a small bowl whisk the soy sauce, broth, brown sugar, rice wine vinegar, garlic, ginger, sesame oil, and red pepper flakes. Pour over ribs in the slow cooker.
Cook on high for 4 hours or on low for 6-8 hours.
Remove the short ribs from the liquid and strain the top layer of fat.
Serve with hot rice, noodles, or mashed potatoes and pour sauce over the ribs and garnish with green onions.
Video
Notes
I recommend this 7qt crockpot.Sear the beef for the best flavor.Place your leftover ginger root in a ziplock freezer bag for more recipes.An easy way to skim the excess fat is to either use a spoon or scoop the top layer of the fat off of the surface of the sauce. or else place a couple of paper towels right on top to soak up the fat.Store any leftovers in an airtight container in the refrigerator for 3-4 days.