Soak the raw mangoes in cold water overnight. Drain the water in the morning and let them dry completely in the sun.
Once dried, chop the dried mangoes into 1-inch cubes.
Add 1 tsp salt and all the turmeric powder and chili flakes.
Mix thoroughly and let it rest in a cool place for about 2 hours.
Meanwhile, dry roast 1 tsp each of mustard seeds, fenugreek seeds, cumin seeds, coriander seeds, onion and fennel seeds till they start giving out a pleasant aroma.
Allow them to cool and then grind coarsely.
Rub the spice mixture thoroughly onto the mango pieces and pour it into a dry jar or bottle.
Top with 2 tbsp of Extra Virgin Olive Oil from Spain.
Keep in the sun for about 12 days, stirring it every day.
This easy mango pickle goes well with meals, paratha, dosa, etc.