In a jar or small jug, put the 15 dried Kashmiri chilies and cover them with warm water; to keep them under the water to soak, choose a container that is slightly wider than a glass, so then you can use a glass to hold the chilies underwater and stop them from floating. Allow the chilies to soak for at least half an hour.
Finely chop the ginger and garlic in small cubes no more than 1,5mm in size; thinly chop the white part of the spring onion as well. Set all aside.
In a pan, warm up the sunflower oil on medium heat, but do not allow it to overheat; once warm add the ginger and garlic and reduce the flame to low. Allow these to cook slowly, without browning, until the rawness has gone (about 2-3 minutes), then add the chopped spring onion.
Mix well and allow to cook on a low flame for a further 4-5 minutes.
In the meantime, drain the Kashmiri Red Chilies, but keep their water on the side; remove the top of the chilies, if the green part is still there, then grind them to a paste using a little bit of the water they soaked in if needed. Put this chili sauce aside.
Once ginger, garlic, and spring onions are cooked, add the Kashmiri chili paste and tomato paste to the pan and mix well again; always keeping them on low heat, cook for a further 4-5 minutes, or until the tomato and chili paste are cooked through.
At this stage add the brown sugar, soy sauce, 1 tbsp of vinegar, and Ajinomoto and mix well; you will need to allow this to cook for a further 5-10 minutes, so add some water from the chilies if necessary.
Once this all has cooked for 10 minutes longer on a low flame, you can add the last half a tbsp of vinegar and adjust the salt. Mix well and cook for a further minute or two, then allow to cool down before storing in the fridge.