Step 1

Heat the oven to 350°F.

Step 2

Divide the beef into 2" pieces. Remove any thick fat deposits, sinew, and gristle.

Step 3

Heat a dutch oven over medium high heat. Add olive oil and heat until it shimmers. Add half the beef, ensuring pieces are in a single layer. Leave undisturbed for at least 5 minutes to sear until a good crust forms. Remove beef to a plate and repeat with the remaining chuck roast pieces. Set aside all browned beef on a plate.

Step 4

Add the onions and leeks to the dutch oven and toss to coat in the fat. Saute, stirring occasionally, until soft, 5-6 minutes. Add garlic; saute, stirring constantly, until fragrant, 1 minute. Add the tomato paste and work into the vegetables.

Step 5

Deglaze the pot with the balsamic vinegar, stirring up the brown bits from the bottom of the pot, until the vinegar stops bubbling and is mostly evaporated, 1-2 minutes.

Step 6

Return the browned beef to the dutch oven. Pour in enough broth to barely cover the beef (about 3 cups), as well as salt and pepper. Give everything a good stir, then add the bay leaf and thyme bundle. All the liquid to come to a simmer. Cover the pot, turn off the burner and transfer to the oven. Braise for 2 hours.

Step 7

Remove the pot from the oven and place onto the stove. Whisk together the cornstarch or arrowroot powder and remaining cup of beef broth, then pour into the stew.

Step 8

Add the chopped potatoes, carrots, and celery. Give the stew a good stir, and again heat over a medium-high flame until the liquid comes to a simmer. Cover and return the stew to the oven to continue braising.

Step 9

Braise an additional 1-1.5 hours, or until the beef is falling apart and the vegetables are tender. Test for doneness around the 1 hour mark.

Step 10

Remove the dutch oven from the stove. Fish out the bay leaf and thyme sprig using tongs. Stir in half to one cup of additional beef broth if the stew is too thick. Taste for seasoning and adjust with salt and pepper if needed. Ladle stew into bowls and garnish with chopped fresh parsley if desired.