Sauce – How to get rid of the raw tomato smell from tomato sauce

Tomato paste is just tomatoes with the water removed, essentially. I'd slice the tomatoes in half and roast them (cut side up) at 350 degrees F for an hour (this will concentrate the flavour nicely and you can add s&p/olive oil/herbs/garlic if you want). Then mash them through a sieve or food mill to get a smooth consistency. Then put that tomato puree in a pot and just boil them down until it's as thick as you want. As it gets thicker, you'll need to stir it regularly to prevent it sticking to the bottom of the pot and burning.

I can give you the Italian answer - first of all, normally we don't use tomato paste to make sauce, but rather to add a tomato "kick" to recipes. Tomato paste is simply tomato puree that has been cooked down to a high degree of concentration.

A basic tomato sauce is made by

1. making a soffritto with onion, carrot and celery (plus other flavors)
2. adding tomato puree, or "pelati", more rarely fresh tomato
3. cooking the sauce down until the taste and thickness is what you want

If you want to use paste instead of puree, the third step has to be omitted or greatly reduced in duration. Keep in mind that tomato paste has its own taste, and that taste will remain in the final sauce.