Heat olive oil in a large saucepan on medium heat. Sauté onions until soft and translucent. Add garlic and Thai chilies and sauté for about 1 minute (do not brown as garlic will become bitter). Add sugar, basil, sage and thyme; continue to cook for another 3 minutes. Crush canned tomatoes; add tomatoes and juice to saucepan. Bring to a boil, then decrease the heat to medium-low and simmer for about 45 minutes, stirring occasionally and skimming off any impurities that rise to the surface. To finish, stir in extra-virgin olive oil. Season to taste with salt and freshly ground white pepper. Remove from the heat and allow to cool.
Can be used right away. Will keep in the refrigerator for 4 days and in the freezer for up to 2 months.
Makes about 3 cups.