Heat the olive oil in a large 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 and add the tomato paste.
Sprinkle in the sugar, salt, and pepper.
Add the dried oregano and bay leaf for flavor.
Bring the sauce to a simmer, then reduce heat to low.
Let it cook uncovered for about 20-30 minutes, stirring occasionally.
Remove the bay leaf and stir in fresh basil leaves.
Adjust seasoning to taste, then serve hot over your favorite dish.