Serves 6 to 8
1. Brown meat: Pat beef dry with paper towels and season with salt and pepper. Heat 1 tablespoon oil in large skillet over medium-high heat until just smoking. Cook half of beef until well browned all over, about 8 minutes. Transfer to slow-cooker insert and repeat with additional 1 tablespoon oil and remaining beef.
2. Brown onions: Add onions, 1 tablespoon oil, and 1/4 teaspoon salt to now-empty skillet and cook until browned, 6 to 8 minutes. Add tomato paste and cook, stirring frequently, until paste begins to darken, about 2 minutes. Slowly stir in broth, soy sauce, and bay leaves and bring to boil. Transfer to slow cooker.
3. Wrap vegetables: Toss carrots, parsnips, potatoes, remaining oil, 1/2 teaspoon thyme, 1/2 teaspoon salt and 1/2 teaspoon pepper in large bowl. Place vegetables on one side of large piece of heavy-duty aluminum foil. Fold foil over vegetables to form packet that will fit in slow cooker; crimp edges to seal. Stir tapioca into slow cooker; set vegetable packet on top of beef.
4. Slow cook: Cover and cook on high until beef is tender, 6 to 7 hours (or cook on low 10 to 11 hours). Discard bay leaves and transfer vegetable packet to bowl. Carefully open packet (watch for steam) and return vegetables and any accumulated juices to slow cooker. Stir in remaining thyme and peas, cover, and let stand until heated through, about 5 minutes. Season with salt and pepper. Serve.