In a large pot or large Dutch oven, heat the olive oil or vegetable oil over medium-high heat. Add the beef cubes, searing them until they are browned on all sides. Remove the browned meat from the pot and set aside. Leave the browned bits from searing the meat in the bottom of the pan.
In the same pot, add the chopped onion and sliced celery. Sauté for about 3 minutes, or until the onion becomes translucent. Add the minced garlic and sauté for another minute.
Return the beef to the pot. Add the 6 cups of water, the bouillon cubes, Worcestershire sauce, bay leaves, thyme, oregano, and parsley. Bring the mixture to a boil, then reduce the heat to low, cover, and let it simmer for 1 hour.
After an hour, add the carrots, potatoes, and peas to the pot. Continue to simmer over low heat for another 45 minutes to an hour, or until the vegetables are tender and the flavors have melded together.
Combine the four tablespoons of flour with 1/2 cup water and stir until smooth. Bring the stew to a boil and add the flour mixture. Cook and stir for 2 to 3 minutes or until thickened and bubbly. Season to taste with salt and pepper.
Remove the bay leaves before serving.