You will need to blanch it for about 4 minutes, and then put it in ice water for about 8 minutes (I actually transfer it to a 2nd ice bath 1/2 through). I remove the ribs and chop first. Once chilled, you will want to spin it in a salad spinner, let it drain, and then roll it in a dish towel to remove as much excess water as possible. I pack it into cubes in an ice cube tray and then put the frozen cubes in ziplock bags. It is okay added to soup, pasta, but is not great as a side when frozen. I can't remember if I added any lemon juice or not--if I did, I added it to the ice water. I searched on the web last year for the best method, and that's what I recall. I have brought kale plants in and over wintered them...you could try doing that as well.