Set slow cooker to low. Line with slow cooker liner (optional). Pat short ribs with a paper towel to remove any excess liquids. Place short ribs into a large Ziploc bag.
Whisk the flour, salt, pepper, and paprika together in a small bowl. Add the dry ingredients to the Ziploc bag with the short ribs, then shake to thoroughly coat them. Set aside.
Pour vegetable oil into a large saute pan over medium heat. Once the oil is hot, remove the short ribs from the Ziploc bag, and brown each side of the short ribs until dark brown and crisped; 1-2 minutes per side. Place cooked short ribs into slow cooker.
Discard of any grease / fat from the saute pan. Leave the browned bits at the bottom of the pan. Add onion, and cook for 2 minutes, scraping browned bits into the onion as it cooks.
Add all other ingredients. Stir to combine. Bring to a low boil, and boil for 1-2 minutes. Remove pan from heat, and pour directly onto short ribs in slow cooker.
Cover and cook for 6 hours, or until meat is tender enough to fall off the bone.
Serve hot over parmesan risotto, or starch of your choice. Veggies are always great, too. :)