Sauté Aromatics: Heat olive oil in a large saucepan over medium heat. Add onion, garlic, and grated carrot. Cook for 3-5 minutes until softened.
Add Tomatoes: Stir in crushed tomatoes, tomato paste, oregano, basil, red pepper flakes, sugar, salt, and pepper. Mix well.
Simmer: Pour in water or broth, reduce heat to low, and simmer uncovered for 20-25 minutes, stirring occasionally.
Adjust Consistency: If the sauce is too thick, add a splash of water. For a smoother texture, blend with an immersion blender.
Finish & Serve: Taste and adjust seasoning. Stir in fresh basil or parsley. Serve over cooked spaghetti or store for later use.