Bring a large pot of water to a rolling boil, then generously salt it. Add the spaghetti and cook until just al dente, about 8-10 minutes. Drain, reserving a cup of pasta water, and set aside.
While the pasta cooks, heat the olive oil in a wide skillet over medium heat. Once shimmering, add the minced garlic and sizzle until fragrant—just about 30 seconds—being careful not to burn it.
Add chopped ripe tomatoes or crushed canned tomatoes to the skillet. Stir and cook for 5-7 minutes, breaking down the tomatoes with the back of a spoon until the sauce thickens slightly and releases a fragrant aroma.
Season the sauce with a pinch of salt and freshly cracked black pepper. Tear the basil leaves and add them to the sauce, stirring gently to release their aroma. Let simmer for another 2 minutes.
Transfer the cooked spaghetti to the skillet with the tomato sauce. Toss well to coat every strand, adding a splash of reserved pasta water if the sauce feels too thick or sticky. Cook together for 1-2 minutes to meld the flavors.
Remove from heat, tear a few fresh basil leaves over the pasta, and drizzle with a little extra olive oil if desired. Serve immediately with an extra crack of black pepper for a fragrant, glossy dish.
