Braised Beef Brisket

Description:
I got this recipe from "The New Best Recipe" book by America's Test Kitchen, and I'm posting this because this is really scrumptious! The beef was so flavorful and tender; this one is truly another no-fail recipe from ATK.

Ingredients:
Beef brisket, about 1.3 kilos, trimmed of excess fat and patted dry with paper towels
Salt and pepper
2 tablespoons vegetable oil
1.3 kilos onions, sliced thin
2 tablespoons brown sugar
6 medium cloves garlic, minced
1 teaspoon tomato paste
1/4 cup unbleached all-purpose flour
1/2 cup dry red wine
1 cup low-sodium beef broth
1 cup low-sodium chicken broth
4 bay leaves
4 sprigs fresh thyme
1 tablespoon cider vinegar



Directions:
Preheat oven to 300F.
Sprinkle the brisket generously with salt and pepper. Heat the oil in a large oven-proof pan until smoking, then cook the brisket until well-browned on both sides. Transfer the brisket to a large plate; set aside.
Reduce heat to medium, then add in onions, brown sugar and 1/4 teaspoon salt. With a wooden spoon, scrape the bottom of the pan to remove the browned bits. Cook until the onions are softened, about 10 minutes.
Stir in the garlic and tomato paste, and cook until fragrant.
Stir in flour and cook for 1 minute, then add in the wine to dissolve the flour. Cook until almost dry about 1 minute, then stir in the broth and herbs.
Bring the brisket back to the pan then bring everything to a simmer.
Cover the pot then transfer to the oven, and cook for 2 1/2 to 3 hours, until meat is super tender that a fork slides easily.
Transfer brisket to a cutting board, tent with foil and let rest for 15 minutes. Slice the brisket across the grain.
Add the cider vinegar to the sauce and serve with the beef.