Trim fat from Oxtails.
Place in a large bowl and drizzle with 1 tablespoon olive oil.
Sprinkle oxtails with onion powder, black pepper, garlic salt, garlic powder and seasoning salt, coating all sides.
Using your hands, massage seasonings into oxtails.
Add oxtails to crock pot.
Add in red wine (or beef broth), tomato sauce and water.
Make sure oxtails are emerged in liquids.
Cover and set timer for six hours.
After 3 hours add in chopped vegetables: carrots, onion and celery.
After 4 hours, stir in ½ cup all purpose flour and then add in potatoes.
Cook two more hours.
When done, garnish with dried parsley flakes.