Cut the tomatoes up, and put them in a saucepan with salt, pepper, garlic, onion, and a bunch of mixed herbs.
Mash them with a fork.
Add no water.
Let them simmer slowly, in their own juice, with the lid on, for about 50 minutes.
Strain through a fine sieve pressing everything through but skin and pips.
Re-heat the purde slowly, adding some more pepper, or Cayenne pepper.
When the pur6e is very thick add the butter and the olive oil.