Baking – Adding lemon to cookie recipe

Three things:

-You can flavor the sugar by mixing aromatic herbs into it and leaving it sit for a week or two. Rosemary pairs well with sweet desserts, as would lavender or basil. Sift out the herbs once you're ready to use the sugar.

-You can try replacing the butter in this recipe (or half of it) with some very good olive oil, as in this recipe from the NYT:

http://dinersjournal.blogs.nytimes.com/2008/03/07/recipe-of-the-day-olive-oil-cookies-with-red-wine-and-rosemary/

That recipe isn't for shortbread cookies, but the technique may still be valid. No guarantees that it will give you the texture you want, but great olive oil has all of the grassy and fruity characteristics that you're after.

-I'm not terribly familiar with matcha, but couldn't you just take some regular green tea leaves and powderize them in a spice grinder?

Use one teaspoon of dried zest for one tablespoon of fresh zest, which is about what you get from a lemon.

Most foods dry to about a third their original size, so I would use one third of the amount called for. Lemons vary a great deal in size, but the recipe probably means one tablespoon of fresh zest, which is normal for "medium" sized lemons.

Something to watch out for is that most cheap "dried lemon peel" products are actually made from the zest and a bit of the pith, which will both give you a bitter flavor and short you some of the lemon flavor you expect. Look closely at the zest you buy, if you can see that the individual pieces have two distinct layers, or a pale yellow or white color, steer clear of that brand. This is probably a "get what you pay for" situation, so spring for the higher end lemon zest.

I have also had great luck drying my own lemon zest. Unless your kitchen is humid, it will probably dry in a day or two just sitting on a plate on the counter.