Heat a drizzle of oil in a large Dutch oven over medium-high heat. Brown the short ribs on all sides until they have a nice crust, about 3-4 minutes per side. Remove and set aside.

In the same pot, add diced onion, carrot, and celery. Sauté for about 5 minutes until softened. Stir in minced garlic and cook for an additional minute until fragrant.

Pour in the red wine, scraping up any browned bits from the bottom of the pot. Allow the wine to reduce for about 2-3 minutes to concentrate the flavors.

Return the seared short ribs to the pot. Add the canned crushed tomatoes, beef broth, thyme, bay leaf, salt, and pepper. Stir to combine well.

Cover the pot and let it simmer on low heat for 3-4 hours. Stir occasionally until the ribs are fork-tender and the sauce thickens.

While the ragu finishes, peel and chop the russet potatoes. Boil them in salted water until tender, about 15-20 minutes. Drain and mash with butter, heavy cream, and Parmesan until smooth.

Spoon the rich ragu generously over the silky Parmesan mashed potatoes. Garnish with freshly chopped herbs and extra Parmesan if desired.

Optionally, drizzle with a little olive oil before serving for an extra touch of richness.