In a large skillet, heat the olive oil over medium-high heat.
Season the beef cubes with salt and pepper. Sear the beef in batches until browned on all sides, about 5 minutes per batch. Remove the beef and set aside.
In the same skillet, sauté the diced onion and minced garlic until softened, about 3 minutes.
In the crockpot, combine the seared beef, sautéed onion and garlic, sliced carrots, cubed potatoes, beef broth, tomato paste, Worcestershire sauce, thyme, parsley, and the bay leaf. Stir to combine.
Cook on low for 8 hours or high for 4 hours, until the beef is tender and the vegetables are cooked through.
Before serving, remove the bay leaf and adjust seasoning with additional salt and pepper if needed.
For a thicker stew, mix 2 tablespoons of corn starch with 2 tablespoons of cold water and stir it into the stew, cooking for an additional 30 minutes on high.