Brown the beef: Heat oil in a pot over medium heat. Add beef and brown on all sides. Remove and set aside.
Build the base: In the same pot, sauté onion and garlic until fragrant.
Simmer the stew: Return beef to the pot. Add tomato sauce, water or broth, bay leaf, salt, and pepper. Bring to a boil, then reduce heat and simmer for 60-75 minutes until beef is tender.
Add vegetables: Add potatoes and carrots. Cook for 10-15 minutes until tender.
Finish and rest: Add bell pepper and simmer for 5 more minutes. Remove from heat and let rest before serving.