Sprinkle beef with salt and pepper. Dredge beef in ½ cup flour.
In a 12-inch cast-iron skillet, cook bacon over medium heat until crisp. Add 4 tablespoons butter, and let melt. Add ribs, and cook until browned on all sides, 3 to 4 minutes per side. Transfer contents of skillet to a 5- to 6-quart slow cooker. Add onion.
In a small bowl, whisk together wine, brown sugar, chili sauce, Worcestershire, beef bouillon, and rosemary; pour over ribs. Cover and cook until tender, about 4 hours on high or 6 hours on low. Remove ribs. Strain cooking liquid from slow cooker.
In a small saucepan, heat remaining 2 tablespoons butter and remaining 1 tablespoon flour over medium heat; cook for 1 minute. Add cooking liquid, and cook, stirring occasionally, until thickened. Serve with ribs. Garnish with rosemary, if desired.
Notes
*We used Better than Bouillon.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/slow-cooker-beef-short-ribs/