Wash and dry the mangoes. Make sure there is no water as this will increase the chances of the pickel getting spoiled
Slice the mango into 2 parts and remove the seeds. I usually leave the hard shell that capsules the seed. But that can be removed if you prefer
Cut the Mangoes into small cubes and set it aside in a big dry mixing bowl
Add in the dry garbanzo beans and methi seeds to the cut mangoes at this point
Now grind the mustard seeds into a smooth powder and set that aside
Measure and add the freshly Ground Mustard powder, chilies powder and Salt to cut mango mix
Give the mix a good toss to make sure the ground masala powders coat the mangoes well
Then measure and add in Gingely oil or Sesame Oil. Adjust oil to ensure that the mangoes are nicely soaked and completely submerged in oil
Let the mix sit for about a week, preferably in a hot dry place where there is good sunlight
This allows the mango and garbanzo beans to pickle in the spice and soak in the flavors