Heat olive oil in a large saucepan over medium heat.
Add chopped onion and sauté until translucent, about 5 minutes.
Stir in minced garlic and cook for another minute.
Add crushed tomatoes and tomato paste, stirring well.
Sprinkle in sugar, dried basil, and dried oregano.
Season with salt and pepper to taste.
Bring the mixture to a simmer, then reduce heat to low.
Let the sauce simmer uncovered for 20-30 minutes, stirring occasionally.
Adjust seasoning as needed before serving.
Serve hot over cooked spaghetti and garnish with fresh basil.