In a tall stockpot, bring 3 quarts of water and 2 tablespoons salt to a boil.
In a separate pot, prepare the tomatoes by bringing a pot of water to a boil and peeling and seeding. Add 2 tablespoons salt to water to loosen skins. Cut a small X on bottom of each tomato and drop one or two into boiling water just until skin begins to curl. Lift out of water and drop into ice-water bath to stop the cooking. Return to boiling water of skins do not slip right off. Use a sharp knife to cut the outside fleshy part of the tomatoes into large pieces and cut them into strips. *If using whole canned tomatoes make sure you strain before adding to the pan.
Drop spaghetti into boiling salted water and stir. Cook until al dente, about 11 minutes.
Place a 12 inch saute pan over medium heat, and add the oil.
Add the garlic to the pan. Cook, stirring occasionally, until garlic is lightly golden, about 30 seconds. Add the red-pepper flakes and remaining 1/4 teaspoon salt. Cook until the garlic is medium golden, about 1 minute.
Increase heat to high. Tilting pan at an angle, add the reserved tomatoes. Cook, swirling pan occasionally, until the tomatoes begin to break down (pear tomatoes will burst and canned tomatoes will thicken).
Drain pasta in a colander, reserving 1 cup liquid in case sauce gets too dry when pasta is added. Add pasta to sauce in saute pan. Cook until the sauce begins to cling to the pasta, 3 to 4 minutes.
Stir in the basil and cook 30 seconds more.
Divide among bowls, and sprinkle with cheese, if desired. Serve.