This was a recipe a turkish friend give me that they used in the shop he worked at in birmingham,it was over 25 years ago so i dont know if its the same as it is now,the problem is it has been that long since i made it i cant remember measurements but it was pretty good,these were the ingredients,
celery
carrot
onion
ginger
garlic
red pepper
fresh tomatoes
tomato puree
chilli powder
paprika
sugar to taste
salt to taste
water
simply put all the ingredients in a blender until it is a smooth paste,then just simmer it for 2 hours,it was much better after it had been left to cool before being chilled,sorry i cant remember the quantities,but i am sure if you wanted to give it a go you could work it out.