Step 1

Preheat the oven to 275°F.

Step 2

In a large dutch oven with a heavy lid, heat the oil over medium heat and wait for it to shimmer. Add flour, salt and pepper on a plate and dredge the oxtails. Use as much or as little flour as you may need, shaking off any excess.

Step 3

When the oil is hot, brown the oxtails on all sides, if necessary in batches, around 4-6 minutes on each side. Remove the oxtails and place them in a plate.

Step 4

Stir in the onions, celery, and garlic and sauté for 5 minutes, until the onions are soft. Pour in the wine and simmer for 5-7 minutes, until partially evaporated.  Return the oxtails and add the tomatoes and broth. Bring to a steady simmer. Cover the pot with crumpled, wet parchment paper, then place the lid securely over the top. Place the dutch oven in the oven.

Step 5

Bake for 2 ½ to 3 hours, making sure the pot simmers very gently. Stir in the balsamic vinegar. Garnish with parsley.