we usually make our own cos i think jarred ones are not very nice, and salty and ummmm gooey?
my tried and tested recipe goes like this:
passatta or chopped tomatos with crushed garlic, tear up some basil leaves and a dollop of olive oil
add a teaspoon of sundried tomato paste if you have it
fry some onions and whatever else (tomatos, meat, mushrooms
peppers, broccoli, courgette, aubergine, grated carrot, whatever you have kicking around really
you can add other stuff to change the taste a bit or put more/less of any ingredients in so go for about 4 garlic cloves haha
you can add creme fraiche, cream or philidelphia if you want it creamy (don't let it boil if you do and mix really well) or chilli powder if you want it a bit spicy (or add chopped peppered salami or something like that).
takes about 10 minutes to do, all you need to do is soften the veg as much as you want them (i like them still a bit crunchy) and the pasta can cook while you are doing it. you can also freeze it if you make loads or put it in the fridge for a few days
oh and you can also make the basic garlic/tomato/oil mixture and put it on pizza bases then just add veg/meat/cheese