Heat the olive oil in a medium saucepan
over medium heat. Add the onion and scallions and sweat for several minutes until the onion is translucent, stirring occasionally so the scallions don't burn. Meanwhile, blanch
the tomatoes in a pot of boiling salted water for 15 to 20 seconds, just long enough so that you will be able to peel the skin. Drain
the tomatoes, and peel
their skins. Then chop
with the garlic and thyme, until garlic and thyme are minced. Add the chopped tomatoes, garlic, and thyme to the saucepan. Stir to combine, adjust heat to a simmer
, and let reduce until thick. Add a pinch of sugar, to taste.