I've noticed from different recipes that people use passata ( which I've never tried) , tomato puree and tinned tomatoes.
What if any are the great differnces of using these three ingrediants.
I've used tomato puree in my last attempt and found that to make a good flavour.

I usually use tinned toms in the base sauce stage.
I would use Passata when making the final curry dish, i might be totally wrong but that usually what i do.

As far as i know Passata is a more concentrated form of tomato puree.

Stew

I have used it a few times and not noticed much difference so use cheap as you can get tin toms instead.

http://www.bbc.co.uk/food/glossary/p.shtml?passata

cK

Passata is simply sieved plum tomatoes, ie tinned tomato's without the seeds, tomato puree however is concentrated tomato flesh, ie with much less liquid and no seeds.

Tomato puree is used as a thickener in tomato based sauces. it has a very concentrated taste and like all tomatoes is quite acidic, when ever you use tomatoes in a dish you should always use a little sugar to add balance to the dish.

Onion

Passata is blended and sieved tinned tomatoes, puree is the more concentrated.  I usually use tinned toms in my base and puree in the final dish too.  CQ

Thanks for that everyone. Sounds like I should stick to tinned toms in my base and puree to finish the dish. Learning little things from people who know and have tried makes it easier for us all on the path to a good curry.

Passatta will give you more flavor i have found in my experiments & therefore give the final dish depth & increased flavor, but experiment with it or you will make your Curries too sweet, this is the tendancy of Passatta if cooked over a long period, especially if you use the Oven method.tendency