Slow-Braised Beef Ragu

In food processor, pulse celery, carrot, onion, and garlic until finely chopped, scraping down side of bowl occasionally. In large skillet, heat oil on medium-high until hot. Sprinkle beef all over with 1/2 teaspoon each salt and pepper. Add beef to skillet; cook 6 to 8 minutes or until browned on all sides, turning occasionally. Transfer beef to 6- to 7-quart slow-cooker bowl. To same skillet, add vegetable mixture and 1/4 teaspoon salt. Reduce heat to medium. Cook 5 minutes, stirring occasionally. Add tomato paste; cook 1 minute, stirring. Stir in diced tomatoes and wine. Cook 2 minutes, stirring and scraping up browned bits. Pour mixture over beef. Add rosemary. Cover and cook on low 10 hours or until very tender. Transfer beef to cutting board. Skim and discard fat from cooking liquid. Remove and discard chunks of fat from beef. Shred beef into bite-size chunks and return to cooking liquid. Serve tossed with pappardelle; garnish with parsley and Parmesan, if desired.