Fill a large pot with water, add a generous pinch of salt, and bring to a rolling boil. This will be your pasta cooking water.
While the water heats, peel and finely chop the garlic cloves. Tear the basil leaves into rough pieces and set both aside.
Add the spaghetti to the boiling water, stirring occasionally to prevent sticking. Cook until al dente, about 8 minutes, until it just starts to taste tender with a slight bite.
While the pasta cooks, heat 2 tablespoons of olive oil in a skillet over medium heat. When shimmering, add the chopped garlic and sauté for about 30 seconds until fragrant and golden, releasing a warm, nutty aroma.
Add the chopped tomatoes to the skillet with garlic, stirring to combine. Season with salt and cook for 10 minutes, allowing the tomatoes to soften and release their juices, creating a slightly chunky, glossy sauce.
Drain the spaghetti using a slotted spoon or colander, reserving about a cup of the pasta water.
Add the drained spaghetti directly into the skillet with the tomato sauce. Toss gently to coat the noodles, adding a splash of reserved pasta water if needed to loosen the sauce and help it cling to the pasta.
Remove the skillet from heat, then tear fresh basil leaves over the pasta and gently toss to distribute. Drizzle with a little more olive oil for shine and aroma.
Taste and adjust seasoning with more salt or freshly ground black pepper as desired. Serve immediately in warmed bowls, garnished with extra basil if you like.
