Why does tomato not dissolve when I make curry when I am cooking curry, I add chopped tomatoes. I cook the tomatoes for 30+ minutes.  In spite of this the tomatoes do not fully dissolve by the end of cooking. There are still whole pieces of tomato that have become cooked but still not become a paste. I have also added water and let the food to simmer, but the tomatoes do not dissolve.

How do I make sure that all tomatoes dissolve into paste when cooking curry?
If Tomatoes aren't cooking quickly. What i do is heat enough oil to high temp and add finely chopped tomatoes and let them cook in oil. Do not add water. Tomatoes have natural water in it. keep stirring till they break down and dissolve. Let all of its water nearly evaporate. Once oil starts separating from tomatoes that means its done.