Heat the olive oil over high heat until it shimmers.
Saute the onions, carrots, and celery, stirring frequently, until they soften and shine, about 10 minutes.
Add the garlic. Stir to combine. Cook an additional two minutes.
Run onions, carrots, celery, and garlic though the food processor to make a paste, and return to pot.
Add the red wine, basil, red pepper flakes, salt, and sugar. Stir to combine.
Add the butter. Stir, cook for about a minute. (Optional)
Add crushed tomatoes, stir, scraping the bottom of the pan to deglaze. Simmer for 30 minutes.
If the sauce seems too thick, add pasta water as needed.
