01 - Preheat oven to 325°F.
02 - Pat short ribs dry and season generously with salt and pepper.
03 - In a large Dutch oven, heat olive oil over medium-high heat. Sear short ribs on all sides until deeply browned (about 3–4 minutes per side). Remove and set aside.
04 - Add onion, carrots, and celery to the pot. Sauté for 5–7 minutes until softened. Add garlic and tomato paste; cook for 2 minutes, stirring.
05 - Pour in red wine, scraping up browned bits. Simmer for 5 minutes to reduce slightly.
06 - Add beef stock, thyme, rosemary, bay leaves, and return short ribs to the pot. Liquid should nearly cover the meat.
07 - Bring to a simmer, cover, and transfer to the oven. Braise for 2–2½ hours, until ribs are very tender.
08 - When ribs are almost done, make the polenta: Bring 4 cups water and salt to a boil in a saucepan. Slowly whisk in polenta. Reduce heat to low and cook, stirring often, for 25–30 minutes until thick and creamy.
09 - Stir butter, Parmesan, and milk into the polenta. Adjust seasoning as needed.
10 - Remove short ribs from the oven. Discard herb sprigs and bay leaves. Skim fat from the surface of the sauce if desired. Serve short ribs over creamy polenta, spooning sauce over the top.