In large pot over medium-high, heat olive oil. Brown beef cubes on all sides, remove from pot, then set aside. Add onion and garlic to pot and sauté until fragrant. Stir in tomato paste and cook for an additional 2 minutes. Return beef to pot and add carrots, peas, and parsnips. Pour in beef bone broth and add bay leaf and thyme. Bring to a boil, then reduce heat and simmer for at least 1 to 1 1/2 hours, or until beef is tender. Stir in sourdough breadcrumbs and cook for additional 10 to 15 minutes, until stew thickens. Season with salt and pepper, to taste.

Serve hot.