Heat olive oil in large pot over medium high heat. Add the onions and sauté until softened. Add smashed garlic and cook for about two minutes. Turn the heat down to medium low, and add the fresh and dry herbs. Cook for two or three minutes.
Add the canned tomatoes and salt and simmer over low heat, stirring often (tomatoes can burn easily).
When the sauce has reduced by a quarter, remove the pot from the heat and blend the sauce with an immersion blender until smooth. Add the sugar. Taste and adjust for salt if required.