Put onion, carrot, celery in a food processor until minced
In a medium saucepan, heat olive oil saute garlic for 2 minutes.
Add the chopped vegetables and herbs.
Cook over low heat for 5 minutes or until the vegetables are softened ant lightly colored
Add the tomatoes ant tomato paste, then add sugar, bring to a boil, then lower the heat and bring to a simmer.
In a medium saucepan, melt butter. Add the flour and cook for 2 minute.
Gradually add the milk, mixing continuously with a wire whisk.
Let mixture boll and thicken a little. Season with nutmeg, salt and pepper,