Prime Rib Roast Beef with Jus | America's Test Kitchen

Ingredients

• 8 pound beef rib roast , meat removed from bone, ribs reserved, patted dry
• 1 1/2 pounds oxtails
• 1 tablespoon tomato paste
• 3 medium onions , cut into eighths
• 3 tablespoons vegetable oil
• 1 1/2 teaspoons kosher salt (preferably) or 3/4 teaspoon table salt
• 2 tablespoons ground black pepper
• 1 cup red wine , medium-bodied, such as Côtes du Rhône
• 1 3/4 cups low-sodium beef broth
• 1 3/4 cups low-sodium chicken broth
• 2 sprigs fresh thyme