For a couple of zucchini and 12 oz of mushrooms, one standard can (16 oz?) of sauce is enough. Good veggies for this: mushroom, zucchini, broccoli, spinach, artichoke heart, green bean, acorn squash. Peppers and onions added to the sauté overwhelm the whole dish for me, making it taste like a big pepper (rather than a big tomato which is what I want it to taste like).
The Saturday afternoon way to get good veggies in sauce (a sauté pan, a pot, a blender, another pot for skinning tomatoes): if I have time I start my tomato sauce by simmering 3 oz of sun-dried tomatoes and a head or two of whole garlic cloves (uncut garlic, cooked before processing, has a much milder taste than garlic that is cut before cooking). A handful of dried sweet red pepper flakes added to this is also good.
Once everything is cooked/rehydrated, I purée it, return it to the pot, add sauteed veggies plus several large peeled/seeded/chopped tomatoes. Also rosemary, basil, oregano, thyme, bay leaves, etc. in random quantities, usually a couple of bay leaves and a couple of teaspoons of each of the dried herbs, and a big wad of fresh basil leaves (hydroponic basil, found year-round in central IL grocery stores). Simmer this until it tastes done. If it's thin, add a little more water and it's soup, if thick, add a little tomato paste and it's spaghetti sauce. I've also put lentils in this and called it minestrone.
- sun-dried tomatoes (optional)
- fresh basil
- canned tomato sauce
- tomato paste
- Grate copious amounts of garlic and sauté in a squirt of PAM spray until brown.
- Sprinkle in some rosemary and oregano.
- Add veggies and some water and sauté.
- Add some fresh basil leaves if you have them, and saute until they just wilt.
- Add a sufficient amount of canned tomato sauce and a little tomato paste to achieve the texture you want.