Preheat the oven to 300°F (150°C).

Season the beef short ribs with salt and pepper. Heat olive oil in a Dutch oven over medium-high heat, add ribs and brown for 3-4 minutes per side. Remove and set aside.

In the same pot, sauté diced onion, chopped carrots, and celery for 5-7 minutes. Add minced garlic and cook for 1 more minute.

Add red wine and scrape the bottom of the pot. Let simmer for 2-3 minutes, then add beef broth, tomato paste, thyme, and bay leaves. Bring to a simmer.

Return ribs to the pot, cover, and transfer to the oven. Cook for 3 hours until fork-tender.

Remove ribs, strain the sauce, skim off fat, serve with sauce, and garnish with parsley.