01 - Generously season beef chunks with salt and pepper on all sides.
02 - Heat olive oil in a large skillet over medium-high heat. Sear beef on all sides until browned, about 2-3 minutes per side. Transfer to slow cooker.
03 - In the same skillet, add onion, carrots, and celery. Cook 4-5 minutes until softened. Stir in garlic and tomato paste; cook 1 minute more.
04 - Transfer vegetables to slow cooker. Add crushed tomatoes, red wine, beef broth, oregano, thyme, bay leaves, and red pepper flakes. Stir to combine.
05 - Cover and cook on low for 8 hours or until beef is very tender and shreds easily. Discard bay leaves.
06 - Shred beef in slow cooker using two forks. Stir to mix thoroughly with sauce. Taste and adjust seasoning with salt and pepper if needed.
07 - About 20 minutes before serving, cook pappardelle according to package instructions. Drain, reserving 1/2 cup pasta water.
08 - Toss cooked pappardelle with beef ragu, adding pasta water as needed to coat. Serve hot, sprinkled with Parmesan and fresh parsley.