Lemon Bars

For the last couple days, I had a craving for lemon bars. Lemon bars are sweet lemony cookies that have a gooey top and a shortbread base. Throughout high school I ate a lot of Lemonheads which are sour lemon hard candies. Perhaps because of this, I like to have my lemon cookies to have a nice and strong lemon flavor. The best recipe for lemon bars I've found is from Baking Illustrated. It is also a simple recipe to execute. 

 Line a 9x13 in. baking pan with parchment paper. The easiest way to do this is to rub some butter on the pan and place a sheet of parchment paper down. Then put some more butter on the parchment paper and place another sheet of parchment paper down perpendicular to the first sheet. This will line all the sides of the pan and not have lemon bars stuck to the side. 

 In a food processor with steel blade, combine 1-3/4 cups all purpose flour, 2/3 confectioner's sugar, 1/4 cup cornstarch, and 3/4 tsp. salt. Pulse a few times to mix. Cut 3/4 cup unsalted butter into 1 inch pieces and add to processor bowl. Process until the flour forms a coarse meal texture (about 12 seconds). Pour the flour mixture into the pan and spread evenly. Using your hands, press down on the flour mixture and compact it evenly to produce a consistent thickness of about 1/4 in. If you like, you can press the mixture up the sides of the pan about 1/2 in., but I don't bother. Refrigerate the crust for thirty minutes to firm it up and then bake at 350°F until golden brown (about 20 minutes).

 While the crust is baking, throw together the filling. We'll be using (from left to right) 2/3 cup lemon juice, 1/3 cup whole milk (do not substitute), 2 teaspoons lemon zest, 4 large eggs, 1-1/3 cups granulated sugar, 3 tablespoons all purpose flour, and 1/8 teaspoon salt.

Whisk together the eggs, sugar, salt, and flour. (Baking Illustrated doesn't integrate the salt at this point - they mix it in with the wet ingredients, but I find it convenient to whisk the salt in with the dry ingredients.)

 Stir in lemon juice, lemon zest, and milk until well blended. Once the crust is done baking, stir the filling once again to make sure it is well blended. Pour filling onto the still hot crust.

 Bake until filling is firm to the touch (about 20 minutes). Remove from the oven and allow to cool to room temperature on a rack. After the lemon bars have cooled, lift the bars out by grasping the free ends of parchment paper and place on a cutting board. Use a pizza wheel or knife, cut into bars. I prefer to cut smaller bars (32 of them) because the filling is quite rich and strong.

 If desired, serve with confectioner's sugar liberally sifted over the bars.