In a resealable bag, combine 1 1/2 tbsp all purpose flour with salt and pepper. Add ribs and shake to coat.
In a large skillet, heat the olive oil over medium-high heat and brown ribs on all sides.
In a large slow cooker, combine onions, carrot, red pepper, wine, chili sauce, brown sugar, vinegar, Worcestershire, dry mustard and chili powder. Mix thoroughly. Add ribs.
Cover and cook on Low for 6 to 8 hours.
Turn the slow cooker to High. Whisk 2 tbsp of flour with 1/4 cup cold water or red wine until there are no more lumps and stir into the sauce. Cook until slightly thickened, about 10 minutes.