- Heat 1 tablespoon of olive oil in a large pot over medium-high heat. Working in batches, brown the stew meat on all sides. Set aside. 
- Add remaining olive oil to the pot. Toss in chopped onions and cook until softened, about 5 minutes. Add garlic and cook another minute. 
- Sprinkle flour over the onion and garlic mixture. Stir well to coat and cook for 2 minutes to eliminate the raw flour taste. 
- Slowly pour in the beef broth while stirring to avoid lumps. Add red wine (if using), tomato paste, thyme, rosemary, and bay leaves. Stir to combine. 
- Return the browned beef to the pot. Bring to a gentle simmer, then reduce heat to low. Cover and cook for 1 hour, stirring occasionally. 
- Add carrots and potatoes. Cook uncovered for another 1 to 1.5 hours, until meat and veggies are tender and broth has thickened. 
- Remove bay leaves. Taste and season with salt and pepper as needed. Garnish with chopped parsley before serving.