Begin by heating a Dutch oven over medium-high heat. Season the beef short ribs generously with salt and pepper, then add them to the pot. Sear the ribs for about 4-5 minutes on each side until they're beautifully browned all over.

Once the ribs are seared, remove them from the pot and set aside. In the same pot, add diced onions and minced garlic, sautéing for 2-3 minutes until the onions are soft.

Deglaze the pot with 1 cup of red wine, scraping up any browned bits. Bring the mixture to a simmer, allowing it to reduce slightly for about 3-4 minutes.

Return the seared short ribs to the pot, adding fresh thyme and rosemary, along with enough beef broth to cover the ribs halfway.

Bring everything to a gentle simmer, then cover the pot with a lid and reduce the heat to low. Let it braise for 2.5 to 3 hours, or until the ribs are fork-tender.

While the ribs are braising, peel and chop the potatoes. Combine them with whole garlic cloves in a pot of cold water. Bring to a boil and cook for about 15-20 minutes until fork-tender.

Drain the potatoes and garlic, then return them to the pot over low heat. Add warm milk and butter, seasoning with salt and pepper to taste. Mash until smooth and creamy.

To serve, spoon a generous serving of creamy garlic mashed potatoes onto each dish. Top with the tender braised short ribs and drizzle with the rich braising sauce.