Preparation

Make the pot roast: Preheat the oven to 300°. Season beef all over with 1 tablespoon salt. Heat 2 tablespoons of the oil in a HexClad 5 QT Dutch Oven over high heat for 2 minutes. Add beef and cook, turning a few times, until golden brown all over, about 12 minutes. Remove beef to a plate. 

Drain excess oil and wipe any blackened bits from the bottom of the Dutch Oven with a paper towel. Return to medium heat and add the remaining tablespoon oil, onion, the carrots cut into 1-inch pieces, and celery. Cook, stirring occasionally, until onion is translucent, about 3 minutes. Add garlic and cook, stirring, until fragrant, about 1 minute more.

Sprinkle flour into Dutch Oven, and cook, stirring, until lightly toasted, about 1 minute. Return beef and any accumulated juices to the Dutch Oven and add wine, broth, thyme, rosemary, and 2 teaspoons black pepper. Increase heat to high and bring to a rolling boil. Cover and transfer to the oven. Bake until beef is fork-tender, about 2½ hours.

Meanwhile make the pickled onion: In a HexClad Hybrid 2 QT Pot, bring vinegar, sugar, 2 teaspoons kosher salt and ½ cup of water to a boil, stirring until solids dissolve. Remove from heat and stir in onion. Let sit at room temperature for 1 hour, then cover and refrigerate until ready to use. 

Remove the beef from the Dutch Oven to a work surface and tent with foil. Set a fine sieve over a large heatproof bowl and carefully strain the liquid into the bowl, pressing on solids to extract as much liquid as possible; discard solids.

Return liquid to Dutch Oven and add potatoes and remaining carrots cut into 3-inch pieces. Bring to a boil over high and reduce heat to a gentle boil. Continue to cook, stirring occasionally, until sauce is thickened and vegetables are very tender, 20 to 25 minutes. 

Using a slotted spoon, remove vegetables to a platter. Slice or shred beef and arrange on platter with vegetables. Serve with remaining sauce in Dutch Oven on the side.