1Heat oven to 325 degrees and line a 9-by-9-inch baking pan with enough parchment to hang over two of the sides.
2To 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.
3Add butter and pulse (or use two knives or your fingers) to cut the butter into the flour until a crumbly dough forms.
4Press dough into prepared pan and bake until shortbread is pale golden all over, 30 to 35 minutes.
5While the shortbread is baking, prepare the lemon curd: Grate ½ tablespoon zest from lemons and set aside.
6Squeeze lemons to yield ¾ cup juice.
7In 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.
8Make sure mixture comes to a boil and stays there for 30 seconds or so; you should see it thicken up before you take it off the heat.
9But once it boils do not cook for longer than 1 minute or you risk the curd thinning out again.
10Remove from heat and strain into a bowl.
11Whisk in butter, olive oil and lemon zest.
12When the shortbread is ready, take it out of the oven and carefully pour the lemon curd onto the shortbread base.
13Return the pan to the oven.
14Bake until topping is just set, 10 to 15 minutes more.
15Allow to cool to room temperature, then refrigerate until cold before cutting into bars.
16Sprinkle with confectioners’ sugar and flaky sea salt right before serving.
Ingredients
1.25 cups all-purpose flour
0.25 cup granulated sugar
3 tablespoons confectioners’ sugar
1 teaspoon finely grated lemon zest
0.25 teaspoon fine sea salt
10 tablespoons cold unsalted butter, cut into cubes
4 to 6 lemons
1.5 cups sugar
2 large eggs
3 yolks
1.5 teaspoons cornstarch
1 pinch fine sea salt
4 tablespoons butter
0.25 cup fruity extra-virgin olive oil
Confectioners’ sugar for sprinkling
flaky sea salt for sprinkling
Equipment
oven9-by-9-inch baking panparchment paperfood processorlarge bowltwo knives or fingerssmall saucepanwhiskstrainer
Tips
Choose an olive oil with personality, something herbal and fresh tasting with peppery notes.
The bars have the brightest flavor when eaten within 24 hours of baking.
When cooking the curd, ensure it comes to a full boil and stays there for at least 30 seconds but not longer than 1 minute to prevent thinning.
Olive oil makes the topping softer, so keep the bars in the fridge until serving.
To easily spread the shortbread, fold down the parchment paper wings and press the dough into place.