Heat the olive oil in a saucepan over medium heat.

Add the chopped onion and sauté until translucent, about 5 minutes.

Stir in the minced garlic and cook for another minute until fragrant.

Pour in the crushed tomatoes, add sugar, oregano, basil, salt, and pepper.

Bring the sauce to a simmer, then reduce heat to low and let it cook for 20-30 minutes, stirring occasionally.

Taste and adjust seasoning if necessary before serving.