Firstly, add oil in a wok and heat it hot enough to deep fry.
When the oil is heated up, add the thinly sliced onions.
Stir for a while.
Fry the onions on medium to sim flame.
Keep stirring them in between to fry them evenly.
Fry them until a pinkish color is observed.
Keep stirring in between so that all the onions are fried well and evenly attain the pinkish color.
At this time be careful as they start getting golden from pinkish within no time.
Be careful and try to remove them as soon as they start changing the color.
When the onions are fried well and start attaining golden brown color take them out.
Place them on a tissue paper and spread them loosely.
Let the oil be absorbed by the tissue paper.
Place them uncovered for 5 - 10 minutes so that they become dry and get the crispy texture to the onions.
When the onions are crispy and crushy, they are ready to be used.
Store them in an air tight container.
They can be used for several days if stored air tight.