HOW TO BLANCH

Blanching simply means placing an ingredient in boiling water and quickly cooling it off in an ice bath to stop the cooking process. Blanching helps in keeping color in vegetables (green beans, asparagus, spinach, peas), drawing out bitterness in earthier plants (kale, collards, mustards) and preps fruits and vegetables for freezing. 

To blanch:

  1. Bring a pot of water to a boil. 
  2. Prepare a large bowl of ice water.
  3. Rinse, trim, or chop fruit or vegetable as directed.
  4. Put items in the boiling water for a couple minutes.
  5. Immediately move to ice water bath to "shock" the fruit or vegetable. 
  6. Drain and pat dry or, in the case of greens and spinach, squeeze the water out of them.

(source:http://localfoods.about.com/od/preparationtips/qt/How-To-Blanch.htm)