In a large bowl or resealable plastic bag, combine the red wine, red wine vinegar, olive oil, sliced onion, minced garlic, sliced carrots, and celery.
Add the beef, making sure it is fully submerged. Cover and refrigerate for at least 4 hours, or overnight for best results.
Remove the beef from the marinade and pat it dry with paper towels.
Heat 3 tablespoons of olive oil in a large Dutch oven or heavy-bottomed pot over medium-high heat.
Sear the beef on all sides until browned, about 5-7 minutes per side. Remove the beef and set aside.
In the same pot, add the chopped onion and cook until softened, about 5 minutes.
Stir in the minced garlic and cook for another minute.
Add the tomato paste and cook for 2 minutes, stirring frequently.
Pour in the beef broth and red wine, scraping the bottom of the pot to release any browned bits.
Stir in the tomato paste, sugar, prunes, olives, and balsamic vinegar. Season with salt and pepper.
Return the seared beef to the pot. The liquid should come about halfway up the sides of the beef; add more broth if needed.
Cover and transfer the pot to a preheated oven at 325°F (160°C).
Braise the beef for about 2.5 to 3 hours, or until the meat is tender and easily shredded with a fork.
Remove the beef from the pot and let it rest for 10 minutes before slicing.
Meanwhile, simmer the sauce on the stovetop to thicken if needed.
Slice the beef and serve with the sauce over potato dumplings or mashed potatoes.
Garnish with fresh parsley.
Enjoy your meal!