Ingredients
240 g all-purpose flour
115 g unsalted butter, room temperature
30 g confectioners' sugar
1.25 ml vanilla extract
1.25 ml salt
2 large eggs
1 large egg yolk
200 g white sugar
30 g all-purpose flour
60 ml freshly squeezed lemon juice
15 ml freshly grated lemon zest
5 ml confectioners' sugar, or to taste
Directions
Step 1
Preheat the oven to 175°C (350°F) and position an oven rack in the middle. Lightly grease an 20x20 cm (8x8 inch) baking dish.
Step 2
To make the crust, combine flour and butter in a large bowl, mashing with a spatula or wooden spoon until well mixed. Add confectioners' sugar, vanilla, and salt, and mix until the mixture resembles slightly crumbly cookie dough. Moisten your fingers with a little water and press the dough into the bottom of the prepared baking dish. Use a fork to prick holes all over the crust.
Step 3
Bake the crust on the middle rack in the preheated oven until the edges are barely golden brown, about 22 minutes. Set aside to cool.
Step 4
For the custard, beat together eggs and egg yolk in a medium bowl until combined. Whisk in white sugar and flour until smooth. Add lemon juice and zest, and whisk for 2 minutes. Pour the custard over the warm crust.
Step 5
Bake on the center rack until the custard is set and the top has a thin white sugary crust, about 25 minutes. Let the bars cool completely before cutting into squares.
Step 6
Dip a knife into very hot water, then run the blade around the edges and cut into 16 squares. Dust the bars with confectioners' sugar.