With a paring knife, remove the stem and then mark an X in the opposite side (bottom) of each tomato. Steam or boil for 2 minutes. Submerge in ice water to stop the cooking. Strain off water and remove skins. Cut in half and remove seeds. Press tomato flat on cutting surface with the palm of your hand, and then dice the tomato meat. Set aside.
Heat a saucepot to medium high. Add olive oil and chopped, diced and minced vegetables except the tomatoes and sauté mixture for 5 minutes, or until soft. Add diced tomatoes, tomato paste and fresh basil. Simmer 20 minutes, or until liquid in saucepot thickens to desired consistency.
Run through a food mill if smooth sauce is desired. Season with salt and pepper. Reserve boiling water that cooked the pasta and use, if needed, to thin and adjust sauce consistency.