Pat the short ribs dry and season generously with salt and pepper
Preheat the oven to 325°F
Heat oil in a large Dutch oven over medium-high heat
Sear the short ribs on all sides until deeply browned
Remove the short ribs and set aside
Add chopped onion, carrot, and celery to the pot
Cook until softened and lightly browned
Add garlic and tomato paste and cook briefly
Pour in red wine and scrape up the browned bits
Simmer until the wine reduces slightly
Add beef stock, bay leaves, thyme, and rosemary
Return the short ribs to the pot
Bring the liquid to a gentle simmer
Cover the pot and transfer to the oven
Braise until the meat is very tender, about 2.5 to 3.5 hours
Remove the short ribs from the pot
Strain or skim the braising liquid if desired
Reduce the sauce on the stovetop until thickened
Serve the short ribs with the sauce over mashed potatoes, polenta, or vegetables