1.
Preheat Oven & Prep Beef: Adjust an oven rack to the lower-middle position and preheat to 300∘F (150∘C).
Pat the beef cubes completely dry with paper towels and season them generously with salt and pepper.
2. Brown the Beef: In a large Dutch oven or heavy-bottomed pot, heat 1 tablespoon of oil over medium-high heat.
Working in two batches to avoid overcrowding the pan, brown half the beef on all sides (about 5-10 minutes).
Transfer the browned beef to a separate bowl.
Add another tablespoon of oil and repeat with the remaining beef.
3.
Cook the Vegetables: To the fat remaining in the pot, add the Portobello mushroom pieces.
Cover and cook over medium heat for 5 minutes until they have released their moisture. Uncover and continue cooking until the mushrooms are dry and well-browned (5-10 more minutes).
4.
Sauté the Aromatics: Add the last tablespoon of oil and the chopped onions to the pot.
Cook, stirring occasionally, until softened, about 5-7 minutes.
Stir in the minced garlic and thyme and cook for 30 seconds more until fragrant.
5. Build the Sauce: Stir in the tapioca flour and tomato paste, and cook for 1 minute. Slowly pour in the red wine, scraping the bottom of the pot with a wooden spoon to release any flavorful browned bits.
Bring to a simmer, then gradually whisk in the beef and chicken broths until the sauce is smooth.
6. Braise in the Oven: Return the browned beef and any accumulated juices to the pot.
Add the bay leaves and bring the stew to a gentle simmer on the stovetop.
Cover the pot, transfer it to the oven, and cook for 1 hour and 30 minutes.
7.
Add Root Vegetables: Carefully remove the pot from the oven and stir in the carrots and turnips. Return the covered pot to the oven and continue to cook for 1 more hour, or until the beef and vegetables are fork-tender.
8.
Finish with Kale: Stir in the sliced kale and return the stew to the oven for a final 10 minutes to allow the kale to become tender.
9.
Rest and Serve: Remove the stew from the oven.
Discard the bay leaves and stir in the fresh parsley.
Let the stew rest for 5-10 minutes to allow the flavors to meld.
Taste and adjust seasoning with additional salt and pepper if needed before serving hot.