In a large bowl, combine the beef chuck cubes with all-purpose flour, salt, and pepper, tossing until the meat is evenly coated.

In a large skillet, heat olive oil over medium-high heat. Add the coated beef and brown each side for about 3-4 minutes until golden.

Using the same skillet, sauté the chopped onion and minced garlic over medium heat for about 3-5 minutes until the onion is translucent.

In the slow cooker, add the browned beef and sautéed vegetables, along with the sliced carrots, cubed potatoes, sliced celery, beef broth, tomato paste, Worcestershire sauce, dried thyme, and bay leaves.

Cover the slow cooker and set it to low heat for 8-10 hours or high heat for 4-5 hours until the beef is fork-tender.

About 30 minutes before serving, stir in the frozen peas if using, and cover again.

Remove the bay leaves before serving and ladle the stew into bowls.