*I only used one cup of sugar- but the original recipe used 1 1/2 cups. If you like your bars nice and sweet- use the full amount. Before using your lemon, you have to do a test to make sure the white part of the skin isn't too thick. (If so the bars may be too bitter. ) Cut your lemon in half- is the white part of the skin especially thick? If the widest part of the white is ¼ inch thick or less, your lemon is good to go. If any part of it is thicker than ¼ inch, however, remove the skin from half the lemon- a little less skin will help to even out the flavor! Recipe slightly adapted from: The Smitten Kitchen Cookbook