01 - Generously season the beef chunks with salt and pepper on all sides.
02 - Heat a large skillet over medium-high heat. Sear the beef on all sides until browned, approximately 3–4 minutes per side. Transfer the seared beef to the slow cooker.
03 - In the same skillet, add the onion, carrots, and celery. Sauté for 4–5 minutes until softened. Add the garlic and cook for 1 minute until fragrant.
04 - Stir in the tomato paste and cook for 1 minute to deepen the flavor. Pour in the red wine, scraping up the browned bits from the bottom of the pan. Simmer for 2 minutes to reduce slightly.
05 - Transfer the vegetable mixture to the slow cooker with the beef. Add the crushed tomatoes, beef broth, oregano, thyme, bay leaves, and red pepper flakes. Stir thoroughly to combine all ingredients.
06 - Cover and cook on low setting for 8 hours, or on high for 4–5 hours, until the beef is fall-apart tender and shreds easily.
07 - Remove and discard the bay leaves. Using two forks, shred the beef directly in the sauce and stir to incorporate. Taste and adjust seasoning with additional salt and pepper if needed.
08 - Cook the pappardelle according to package instructions until al dente. Drain the pasta, reserving a small amount of cooking water. Toss the pasta with a ladle of the ragu sauce to coat.
09 - Plate the pasta topped generously with the beef ragu. Garnish with freshly chopped Italian parsley and grated Parmesan cheese.