Wash and wipe all mangoes. Now peel off skin of mangoes.
Grate mangoes with medium sized grater. Keep it in a large wooden pot / steel / food grade plastic pot.
Take a clean wet kitchen towel. Now wipe Bengal gram and fenugreek seeds. Spread in a dry plate for 5 minutes.
Take out 1.5 tbsp fenugreek for powder. Put rest of fenugreek, Bengal gram, turmeric powder, salt in grated mango. Stir very well and keep aside for overnight. Do this process in evening / night .
Heat a heavy bottom pan on high flame then reduce flame on medium heat.
First put fenugreek seeds in pan then dry roast for one minute. Add fennel seeds to pan ; dry roast till aroma comes out. Now add mustard seed stir well. Switch off the gas. Take out all ingredients in a plate then cool it down in fan air.
Put in a dry grinder jar and make fine powder. Take out in a plate and cool down.
Heat oil in a pot or kadai on high flame till smoke comes out . Now add hing in oil and heat for another one minute. Switch off the gas stove. Cool down naturally. Do these work according to your free time.
In morning we will add all spices as mustard, fenugreek, fennel powder, both chilly powder, ajwain, kalonji, fennel seeds and half oil in mango mixture. Stir well with help of wooden / plastic spoon so that all spices will be mix properly.
Keep this pot in full sunlight for at least 4-6 hours for 3 days. Stir 4-5 times when pot is in sunlight.
After 3 days add rest of oil in pickle and stir properly so oil will coat evenly.
Check salt of pickle then adjust as per your preference.
Keep pot in sunlight for another 3-4 days according to mango quality. Now keep this pickle in clean - dry glass bottle. Tie muslin cloth in the neck of bottle.
Keep it as it is in sunlight for another 2 - 3 days. When bottle is completely cool down then remove muslin cloth and put its own lid.
Use clean and dry spoon for take out pickle. This pickle lasts for longer period more then one year.
Enjoy this unique style pickle with various types poori, paratha, roti and rice.