Remove root, top and skins and sliced into thin slices.
And take cotton cloth and spread sliced onion evenly.
And get dried under sun for 2-3 days or till completely dry.
Yoy can also dry in preheat oven at 140℃ degree.
When the pieces are dry let them cool before you them in container.
Put them in a storage container or zip bag for one year.
For recipe used- Take required quantity and add water level should be 1-2 cm higher than onion.
One onion makes about 1/4 cup of dreied onions. Means 4-5 tbsp dry onion is equal to one medium size onion.
If yor recipe calls for a whole onion you would take 1/4 cup of dried onion and add 1/4 cup of boiling water and soak for 15 minutes.
Just leaves it in water until it's absorbed all water.
You can use this onion in any dish like gravy, dal, sabzi, fries veg. and non-veg food.