basque oxtail stew

basque oxtail stew
serves 4-6

3 tbsp canola oil
4 lbs oxtail, trimmed
salt and freshly ground pepper to taste
4 cloves garlic, finely chopped
1 large onion, finely chopped
2 cups dry red wine
6 cups chicken stock
1 8 oz can tomato sauce or pureed diced tomatoes, drained
6 medium carrots, sliced 1/2" thick
1/4 cup flour
4 tbsp butter, softened

Heat oil in an 8-qt. saucepan over medium-high heat. Season oxtail with salt and pepper; working in batches, cook, turning as needed, until browned, 8–10 minutes. Using tongs, transfer oxtail to a plate; set aside. Add garlic and onion to pan; cook, stirring occasionally, until golden, 6–8 minutes. Add wine; cook, stirring and scraping browned bits from bottom of pan, until reduced by a third, 3–4 minutes. Return oxtail to pan and add stock, tomato sauce, salt, and pepper; bring to a boil. Reduce heat to medium-low; cook, covered, until oxtail is tender, 2 1⁄2–3 hours. Uncover and return to a simmer. Add carrots; cook until tender, 15–20 minutes. Mix flour and butter in a bowl until smooth; stir into stew and cook until slightly thick, 8–10 minutes.