Generously season beef short ribs with salt and pepper and let sit for about 30 minutes.

Heat oil in a Dutch oven over medium-high heat, then sear short ribs until browned, about 4-5 minutes on each side.

Sauté diced onions and minced garlic in the same pot until soft, about 5 minutes.

Deglaze with red wine, bring to a boil, and simmer for 5 minutes until reduced by half.

Return the ribs to the pot, cover halfway with beef broth, and add thyme, rosemary, salt, and pepper. Simmer gently for 2.5 to 3 hours.

While ribs are braising, cook peeled and chopped potatoes and garlic in salted water until tender, about 15-20 minutes.

Mash potatoes and garlic with butter and milk until smooth, then season with salt and pepper.

Serve braised ribs over garlic mashed potatoes, drizzling with braising sauce and garnishing with fresh herbs.