Makes 4 servings
In a sauce pan, heat the olive oil and onion or shallot on medium heat. Cook until it turns a light golden color. Add the celery and carrot, stirring to coat, and cook for another 2-3 minutes. Next, stir in the tomatoes, reduce the heat to a simmer, and cook for 45 minutes.
Stir the sauce from time to time to prevent any sticking on the bottom of the pan. The sauce will thicken and become darker in color. Once the sauce is done cooking, taste and season with sea salt. Cook the pasta in well salted water until al dente and drain (always reserve a little pasta water just in case you need to thin out the sauce a bit). Toss the hot pasta with the tomato sauce to coat. If you like, top with fresh parsley and Parmigiano Reggiano.