Clean the kale leaves with running water (We only have to use leave not the stem). Boil 4 cups of water in a pot, add 1/2 tsp salt and 1 tbsp lemon juice. Once it start boiling, blanch the kale leaves one by one for 30 sec, so that the bitterness goes away. Remove the leaves from the hot water, drain it and add some ice cubs in it immediately. Once leaves gets cool, squeeze water out from the leave and chop it very fine.