Pat the beef chuck cubes completely dry with a paper towel and season evenly with sea salt and black pepper.
Heat the avocado oil in a large Dutch oven over medium-high heat and sear the beef in batches until a deep brown crust forms on all sides.
Remove the beef and set aside; add the diced onion, carrots, and parsnips to the pot, sautéing for 5 minutes until the edges are golden.
Stir in the minced garlic and tomato paste, cooking for 60 seconds until the paste turns a dark brick red and becomes fragrant.
Pour in the beef bone broth and use a wooden spoon to scrape up all the flavorful browned bits (fond) from the bottom of the pot.
Return the beef and any accumulated juices to the pot, then add the dried thyme, dried rosemary, and the bay leaf.
Bring the liquid to a gentle boil, then immediately reduce the heat to low, cover tightly, and simmer for 75 to 90 minutes until the beef is succulent and fork-tender.
Remove the bay leaf before serving the stew in wide, warmed bowls.