Heat the olive oil in a large saucepan over medium heat until hot but not smoking.
Add the finely chopped onion, finely chopped celery, and minced garlic to the pan and cook, stirring occasionally, until the vegetables are tender, about 5 minutes.
Add the canned crushed tomatoes, roughly chopped basil, salt, and black pepper to the saucepan and stir to combine.
Bring the sauce to a boil over medium-high heat, then reduce the heat to low and cover partially.
Let the sauce simmer gently on low heat, uncovered or partially covered, for 40 minutes, stirring occasionally.
Remove the sauce from the heat and serve immediately, or let it cool completely before storing.