Crockpot Beef Brisket

4 lb beef brisket 
4 cloves garlic, minced
2 Tablespoons ketchup
1 Tablespoon red wine vinegar
1 Tablespoon brown sugar
1/2 teaspoon salt
1/8 teaspoon pepper
2 onions, thinly sliced
1 Tablespoons flour
1/3 cup water

Place onions in bottom of crockpot, then place brisket, fat side up, on top of onions.  Sprinkle garlic on top.   Add salt and pepper to brisket.  Combine ketchup, vinegar and brown sugar in small bowl and then rub into beef.  Add enough water to coat the bottom of the crockpot.  Cover and cook on low 8 to 10 hours.

For gravy, remove brisket from the crockpot, place on serving plate and cover tightly with foil.  Turn crockpot temperature to high.  Mix flour with a1/3 cup water, add to crockpot and bring to a boil, stirring frequently with wire whisk.