Bring a large pot of salted water to a boil over high heat.
In a large skillet with a lid, heat olive oil over medium-high heat. Once hot, add onion and cook until softened, about 3 to 4 minutes, stirring occasionally. Add garlic, cooking until fragrant, about 30 seconds to 1 minute.
Stir in tomatoes. Make sure to stir the tomatoes in well so the oil incorporates into them to make the sauce. Season with salt and pepper. Cover and simmer over low heat for about 10 minutes.
While the sauce is simmering, cook the pasta until al dente, according to the instructions on the packaging. Reserve 1 cup of pasta water and drain the rest. Set aside.
Stir basil into sauce and simmer for 5 more minutes. Remove from heat. If the sauce got too thick during the simmering process, add in a splash of pasta water to loosen it up.
Toss cooked noodles in the sauce to coat well.
Serve with grated parmigiano reggiano and freshly chopped basil.