Heat olive oil in a large saucepan over medium heat.
Add chopped onions and sauté until translucent.
Stir in minced garlic and cook for an additional minute.
Add crushed tomatoes to the pan, stirring well.
Season with oregano, basil, salt, and pepper.
If desired, add sugar to balance acidity.
Bring the sauce to a simmer and reduce heat to low.
Let it cook for 20 minutes, stirring occasionally.
Taste and adjust seasoning as needed.
Serve hot over pasta or as a pizza sauce.