Staples: Pomi Strained Tomatoes
The best brand avaialble locally is Pomi (made by Parmalat, best known for its milk products), which is 100% tomatoes, no salt, preservatives, or seasonings. Even homemade sauce made from peak-season plum tomatoes would be hard-pressed to match the intense, rich flavor of this puree, which is superior to any canned tomatoes or tomato paste I've had, imported or domestic. Pomi's skinned and seedless chopped tomatoes are similar but have a chunky rather than smooth texture. Both come in 750-gram (26 oz.) boxes. Most places charge around $4 a box, but shop around and you can find it for closer to (and sometimes under) $3. I don't recommend the Pomi marinara sauce.
A good way to appreciate the flavor is with this super-simple pasta sauce:
Simple Tomato Sauce
2 tbsp. finely diced onion
2 tbsp. olive oil
1/2 box Pomi strained or chopped tomatoes
a few basil leaves or sprigs of marjoram, oregano, or thyme (optional)
salt to taste
Saute the onion in the olive oil until translucent. Add the tomato, herb, and salt. Simmer gently for 20 minutes, uncovered. Adjust salt. Serve on spaghetti with freshly-grated Parmesan.
Variations: crushed red pepper and/or garlic with the onion; add 1/4 cup finely chopped parsley with the tomatoes.