The first dessert I ever made from scratch were lemon squares. The recipe came from my very first cookbook, The Absolute Beginner’s Cookbook, Revised 3rd Edition: Or How Long Do I Cook a 3 Minute Egg?. I had never really had lemon squares (or lemon bars) before. It’s not a dessert I grew up with. But I was instantly hooked. I loved the shortbread crust and the intensely tart and sweet filling. Over the years I made that recipe a lot but as my tastes became a little more sophisticated, I started to find the lemon squares too rich and cloying for me. So I stopped making them.
Then, about a year and a half ago, the amazing Melissa Clark of the New York Times posted a recipe and a video where she made lemon squares (or bars, as she called them), using both butter and olive oil and topping them with a touch of flaky sea salt. Steve was instantly smitten and he has been asking for them ever since. We finally got around to making them a couple of weeks ago. They are, of course, fantastic. The olive oil adds some adult notes to the curd filling and the salt kicks everything up a few notches. The only problem was that these had to be eaten fairly soon, and even for us, that would have been too much dessert. So, we though we’d try and freeze them, thinking that it wouldn’t work because the filling with ooze once it thawed.
We were so, so wrong. One day later, I reached into the freezer drawer and gently pressed on the top of one of the lemon squares. The filling wasn’t frozen at all. It was still soft. All that sugar and fat prevented it from freezing. So, I pulled two lemon squares out of the freezer and we both took a bite. That was a seminal moment in our lives…as far as lemon squares are concerned. The (not so) frozen treats were so much better than their merely refrigerated versions that I doubt we will ever eat them any other way. The cold temperature tempers the sweetness and the filling has a little more structure to it. The shortbread crust is not too hard to bite into. The whole thing is irresistible.
Frozen Lemon Squares with Olive Oil and Sea Salt – Very slightly adapted from the New York Times
FOR THE CRUST:
1 ¼ cups/155 grams all-purpose flour
¼ cup/50 grams granulated sugar
3 tablespoons/25 grams confectioners’ sugar, plus more for sprinkling
1 teaspoon finely grated lemon zest
¼ teaspoon fine sea salt
10 tablespoons/142 grams cold unsalted butter, cut into cubes
FOR THE CURD FILLING:
4 to 6 lemons
1 ½ cups/300 grams sugar
2 large eggs plus 3 yolks
1 ½ teaspoons/5 grams cornstarch
Pinch of fine sea salt
4 tablespoons/57 grams butter
¼ cup/60 milliliters fruity extra-virgin olive oil
Flaky sea salt, for sprinkling
Heat oven to 325 degrees and line a 9-by-9-inch baking pan with enough parchment to hang over two of the sides (to be used as handles later to lift the bars out of the pan).
To make the shortbread base, pulse together the flour, granulated sugar, confectioners’ sugar, lemon zest and salt in a food processor, or whisk together in a large bowl. Add butter and pulse (or use two knives or your fingers) to cut the butter into the flour until a crumbly dough forms. Press dough into prepared pan and bake until shortbread is pale golden all over, 30 to 35 minutes.
While the shortbread is baking, prepare the lemon curd: Grate 1/2 tablespoon zest from lemons and set aside. Squeeze lemons to yield 3/4 cup juice.
In a small saucepan, whisk together lemon juice, sugar, eggs and yolks, cornstarch and fine sea salt over medium heat until boiling and thickened, 2 to 5 minutes. Make sure mixture comes to a boil or the cornstarch won’t activate. But once it boils do not cook for longer than 1 minute or you risk the curd thinning out again. Remove from heat and strain into a bowl. Whisk in butter, olive oil and lemon zest.
When the shortbread is ready, take it out of the oven and carefully pour the lemon curd onto the shortbread base; return the pan to the oven. Bake until topping is just set, 10 to 15 minutes more. Allow to cool to room temperature, then refrigerate until cold before cutting into bars.
At this point they are ready to eat. Sprinkle with confectioners’ sugar and flaky sea salt right before serving. However, do yourself a favor and put them all in the freezer in one layer (before sprinkling confenctioner’s sugar and salt and them) and leave them there for 24 hours. At that point, you can serve them straight from the freezer. Sprinkle with confectioner’s sugar and flaky sea salt and enjoy.