Step 1

Heat the olive oil in a large heavy-bottom pot or dutch oven over medium-high heat.

Step 2

While the oil is heating up, add the beef stew meat to a large mixing bowl and sprinkle over the flour, salt, and pepper and stir to coat.

Step 3

Working in three batches, add 1/3 of the meat to the pan and sear, turning with tongs until browned on all sides for about 4-5 minutes per batch. Set all of the meat aside on a clean plate.

Step 4

Reduce the stovetop heat to medium

Step 5

Add the butter to the pot along with the chopped onion, cook, stirring occasionally for 2-3 minutes until softened.

Step 6

Add in the garlic and cook, stirring constantly for 30 seconds. Then, stir in the tomato paste and cook for one more minute.

Step 7

Pour the red wine into the pot and use a wooden spoon to scrape up any browned bits from the bottom of the pan.

Step 8

Pour in the beef stock, Worcestershire sauce, balsamic vinegar, bay leaves, thyme, and return the seared beef to the pot. Stir to combine.

Step 9

Reduce the heat to low (medium-low), cover and simmer for 60 minutes until the beef ins becoming tender.

Step 10

After 60 minutes, stir in the carrots, potatoes, and mushrooms.

Step 11

Cover and simmer for 30 more minutes until vegetables are tender.

Step 12

If desired for a thicker stew, whisk together the cornstarch and cold water in a small bowl, then whisk into the stew for 1-2 minutes until thick.

Step 13

Brown the meat as directed above and place in the bottom of a 6 quart or larger slow cooker.

Step 14

Follow directions 1-4 from the stove top version, then add all of the remaining ingredients to the slow cooker with the meat.

Step 15

Cover and cook on low for 6-8 hours until meat is tender.

Step 16

During the last 30 minutes of cooking time, turn the slow cooker up to HIGH.

Step 17

Whisk together the cornstarch and cold water, then whisk into the stew and allow to simmer for 30 minutes.