Begin by patting the beef chuck cubes dry with paper towels. Season the beef generously with salt and pepper, and toss lightly in flour if desired.

Heat 2 tablespoons of oil in a skillet over medium-high heat. Brown the beef cubes for about 2-3 minutes per side until caramelized.

In the slow cooker, layer chopped onions, minced garlic, diced carrots, and cubed potatoes beneath the browned beef.

In a separate bowl, combine beef broth, optional red wine, tomato paste, Worcestershire sauce, thyme, salt, and pepper. Stir well and pour over layered vegetables and beef.

Cover the slow cooker and cook on LOW for 6-8 hours or on HIGH for 3-4 hours.

For a thicker stew, mix 2 tablespoons of cornstarch with 2 tablespoons of cold water to create a slurry, then stir into the stew.

Taste and adjust seasoning with extra salt and pepper, then let the stew rest for 10-15 minutes before serving.