I made them for our party on Friday (which was excellent by the way), and thankfully there were still a few left over.
This cookie was featured in December's Gourmet magazine, and unfortunately I must say, my photos are not quite up to par with theirs (click through to compare). But they were just as good (I think), even though I accidentally added an extra tablespoon of lemon juice to the icing. The other really great thing that happened while making these cookies (aside from the copious amount of Christmas music I was listening to) was that I realized I had used up all the eggs making the latkes earlier in the week. I didn't want to leave the apartment, so I considered running downstairs to borrow from the neighbors, until I realized these cookies require no eggs. Life never seems to work out like that, isn't it great when it does?
Lemon Sandwich Cookies: 1 1/3 cups all-purpose flour 2/3 cup cornstarch 1/4 teaspoon salt 2 sticks unsalted butter, softened 1/2 cup powdered sugar 1 tablespoon grated lemon zest 1 teaspoon vanilla White or colored sanding sugars (for icing): 1 cup powdered sugar 1 tablespoon grated lemon zest 1 tablespoon fresh lemon juice 2 tablespoons light corn syrup 1/2 stick unsalted butter, softened
Preheat oven to 350 degrees. Whisk together flour and corn starch. In a separate bowl, mix together butter and sugar, beat in lemon peel and vanilla. Gradually add flour mixture to sugar mixture until blended.
Put sugars in separate bowls. Roll a "scant" teaspoon of dough into a ball, drop into sugar and turn to coat. Bake cookies in the oven for 12 to 15 minutes, until the tops are cracked and the bottom is golden.
For filling, combine all ingredients in a bowl and mix until blended. Transfer to a piping bag (or, as in my case, a big Ziploc), snip the corner and apply to flat side of one cookie. Sandwich with a matching cookie. Try not to eat too many before your party. Use a healthy amount of icing to glue the two cookies together--there will be some left over.