Pat the short ribs dry with paper towels, and season generously with seasoning listed above on all sides.
Heat olive oil in a large, heavy-bottomed pot. Once the oil is hot, add the short ribs in batches (do not overcrowd the pan) and sear on all sides until browned, about 3-4 minutes per side.
Remove the short ribs and set them aside.
In the same pot, reduce the heat to medium and add the sliced onions, green bell peppers. Cook until they are softened and beginning to caramelize, about 5-7 minutes.
Add the minced garlic and cook for another minute until fragrant.
Sprinkle the flour over the onions, peppers and garlic, stirring constantly for about 2 minutes to cook out the raw flour taste.
Slowly pour in the beef broth stirring to deglaze the bottom of the pot and incorporate the flour.
Season with salt and pepper to taste. Bring the mixture to a simmer.
Add the seared short ribs back into a baking dish. Pour gravy over ribs to ensuring they are mostly submerged in the gravy.
Cover the pot with a lid and place in a preheated oven at 350 degrees.
Let the short ribs cook for 2 to 3 hours, or until the meat is tender and falling off the bone.
Serve the flanked beef short ribs smothered in the rich, flavorful gravy. Garnish with chopped fresh parsley if desired.