Place the olive oil and garlic in a 2-quart saucepan over medium heat. Swirl the pan to coat the garlic with oil and heat until garlic sizzles but doesn't brown, about 30 seconds. Add the red pepper flakes and stir. Add the tomatoes, salt, black pepper, and sugar and stir to combine. Bring to a boil and reduce the heat to a simmer. Cook for at least 20 minutes but no more than 30. Add the basil for last 5 minutes of cooking. Remove the basil before serving.
Meanwhile, with 10 minutes to spare before the sauce is done, generously salt the boiling water. Add the pasta and cook until tender but slightly firm. Set the timer for 2 minutes less than the package instructions specify and taste for doneness. Drain the pasta and transfer it to a serving bowl. Toss with 1/2 cup of the sauce. For each serving, spoon on a little extra sauce, grated Parmesan cheese, a drizzle of olive oil, and freshly ground black pepper on top of the pasta.