Wash and wipe dry the tomatoes . Cut the tops of the tomatoes, and using a food processor or knife, chop each tomato into 1/8, coarsely puree them with some chunks intact. do NOT add water at all at any stage during the entire pickle making process.
Dry roast the ingredients one by one under spice powder mix. Ensure the methi seeds are not burnt else will taste bitter. If you need to roast the red chillies in oil, add 1/2 tsp of oil and fry on a low flame. Cool thoroughly and powder
In a deep pan, add half of the sesame oil. Splutter the mustard seeds and the asafoetida. Now add the coarse tomato chunk+puree mixture and turmeric. Stir once or twice, and let it cook covered for 8-9 mins covered till they are almost reduced by a third.
Now add the spice powder, 1/2 of the remaining oil, mix gently and let it cook on a low flame for next 10-12 mins on a very low flame till oil starts separating from the sides. (it would require your continuous watch over the stove at this stage, it may also splutter as the mixture gets thicker, so you may want to cover the pot while stirring every 30 seconds.)
When you see the original quantity of tomatoes reduce to 2/3 or even half, add in the remaining oil, salt, jaggery. Mix and do a taste test and adjust spices accordingly.
At the end of this stage, oil should start floating to the top (it will settle once bottled, so dont worry).
Cool thoroughly and bottle in a sterile glass bottle.
Refrigerate and use a portion with a sterile clean dry spoon as required. stays for 2-3 weeks under refrigeration