for tomato sauce. I learned to do this as a bachelor, but I've gotten raves for it.
Take one can (whatever size you like) of whole peeled tomatoes. Open the can.
Get a skillet or frying pan of some sort and set it at medium heat. When a drop of water sizzles when it hits the pan, remove the tomatoes one by one from the can and smoosh them over the pan. I usually throw the liquid in the can away, but you can reuse it for something else if you want.
Add anything else that you think might be tasty. I've used browned ground beef, prosciutto ham, garlic, olive oil, cumin, cilantro, basil, really the skies the limit.
Cook the smooshed tomatoes until they look like a sauce.
You're done. Enjoy!