Trim roast of excess fat, cut into 1" cubes. Allow to come up to room temperature.

Pat beef cubes dry with a paper towel, season well with salt and pepper.

Measure about 1 tablespoon of the oil into a large, heavy bottomed pot. Heat over a high fire.

Add the beef to the heated pan. Sear, stirring occasionally, until browned all over.

Once browned on a splash of the beef broth to the pan, scraping and stirring the beef drippings - this is called deglazing.

Once the beef is all scraped off the bottom of the pan and incorporated, add remaining beef broth and the bay leaves.

Bring to a boil, then reduce fire to maintain a low simmer. Simmer over a low fire for 1 ½ hours, or until meat is very tender.

As the beef cooks, prepare your vegetables: Quarter or slice the mushrooms, peel and chop the turnips, chop the celery, peel and slice the carrot, chop the onion, press or mince the garlic, and cut the Brussels sprouts in half.

Once beef is tender, add all of the vegetables - except the Brussels sprouts - to the pot, stir to combine.

Bring it to a boil again, then turn heat back down to low and simmer for another 30 minutes or so. Add Brussels sprouts, continue simmering another 10 minutes, or until the vegetables are tender.

In a small bowl, combine the starch, dried parsley, dried thyme, and dried rosemary. Be sure to stir well - you want the starch (or xanthan gum) well distributed over the other ingredients, to prevent clumping.

Add herb mixture to the pot, stir well to combine. Allow stew to simmer for a few minutes to thicken.