Once upon a time there were tinned tomatoes and, lo, they were an common sort of food eaten in transport cafes with bacon and a fried slice. And Elizabeth David did visit the Mediterranean and discovered sweet luscious red plum tomatoes and was mightily wrought by them and did market the idea of them in her gastroporn works of the lean post-war years when Britons did eat Spam and other abominations. And we did read her words and agreed with them, but for many moons no such tomatoes existed in this land save in the imagination. But what of the lowly tinned tomatoes? Did they not come in the main from those same exotic lands of which Mrs David did write with such joy? Indeed they did and indeed they do; and without much work they can be converted into a very passable sauce that shouts, ‘Food of the sun!’ A teensy bit of sugar helps them shout louder.
In recent times we have seen the introduction of jars and packets of passata, which is simply peeled and sieved tomatoes. Passata consequently does not have an intense flavour and needs to be cooked down before it can be used to good effect in a sauce. After reduction, however, you will end up with a similar result to that achieved using tinned tomatoes. You cannot, however, create pieces of tomato by cooking passata, so tinned tomatoes give you greater flexibility of use. If you put the contents of a tin of tomatoes in the blender or processor and whizz them up you will have passata plus pips. Put this mulch through a sieve and you have passata.
Once you get in the habit of making this sauce regularly you can forget about tomato puree. Try dispensing with the caster sugar in the recipe and substituting 2 tablespoons of good-quality tomato ketchup to give it an extra flavour boost.