Preheat oven to 350°F.

Heat the vegetable oil over medium-high heat in a large dutch oven or stock pot. Add the short ribs and brown them on all sides until caramelized. Remove the ribs from the pot and set aside.

Reduce the heat to medium and add the diced carrots, celery, and onion. Cook for about ten minutes until softened. Add the garlic and cook for another couple of minutes.

Stir in the tomato paste until all of the veggies are coated. Sprinkle in the flour and stir to coat all of the vegetables. Cook for another few minutes.

Pour in the wine and increase heat until the pot begins to simmer. Deglaze the pot by scraping the bottom with a spatula.

Add the tomatoes and all of the juice from the can. Pour in 2 cups of water and stir, breaking up the tomatoes with a wooden spoon or spatula.

Add the short ribs back to the pot, ensuring they are completely covered by the liquid. Add parsley and stir.

Bring to a strong simmer, cover, remove from heat, and transfer to the oven. Simmer for 2 to 3 hours or until the beef is fork-tender.

Once tender, remove the pot from the oven. Remove the short ribs and strain the liquid into a large sauce pot. Discard the solids.

Bring the sauce to a simmer over medium-high heat and reduce for about 30 minutes, skimming fat periodically.

Shred the short ribs. Once the sauce thickens, add the shredded meat and stir.

Fill a large pot with water and bring to a boil. Add the potatoes and boil until fork-tender, then drain.

Return the potatoes to the pot, add butter, and mash. Stir in sour cream and parmesan cheese. Season to taste with salt and pepper.

Serve the ragu on top of the parmesan mashed potatoes. Garnish with chopped parsley.