A rich version of the lemon bars recipe.

My ideal lemon squares are anchored with a buttery shortbread crust that’s just sweet enough. The dry ingredients come together quickly in a food processor. After pulsing in the butter (plus an egg yolk for richness), the mixture will look powdery but should hold together when you squeeze a handful. (If it doesn’t, add cold water 1 tsp. at a time, pulsing between each addition.) This is just the right consistency for pressing into the bottom of a parchment-lined baking dish (I prefer 20 x 20 cm for thicker layers).

For maximum lemon flavor, you’ll rub the lemon zest into the sugar with the tips of your fingers, extracting the lemon oils and allowing them to permeate the filling.

You’ll pour the tart lemon filling on top of the still-warm shortbread, then continue baking until the curd is set and the crust is crisp. Set a timer for 5 minutes after pulling the crust from the oven to ensure it doesn’t cool too much—if the shortbread is allowed to reach room temperature, the uncooked lemon curd will slip off the top and pool in the bottom of the dish, turning your lemon bars upside down (sounds bananas until it happens to you!). After pouring in the lemon mixture, tap the baking dish on the counter to pop any lingering bubbles before transferring the lemon bars to the oven.

A final dusting of powdered sugar adds a nice touch, but hold off until you’re ready to serve, lest the sugar disappear into the lemony depths.

Ingredients Crust

Directions

• Place a rack in middle of oven; preheat to 162° celsius.

• Line a 20 x 20 cm baking pan with parchment paper, leaving overhang on all sides.

• Pulse the flour, powdered sugar, and salt in a food processor to combine.

• Add the unsalted butter and pulse until mixture is sandy with very small butter pieces.

• Add 1 large egg yolk and pulse until combined; mixture will be very dry looking and powdery but should hold together when squeezed in your hand.

• Transfer mixture to prepared pan and spread into an even layer to fill pan. Using a flat-bottomed measuring cup or glass, pack into a compressed layer (use your fingers to get into the corners). Bake crust until golden, 27–29 minutes. Let cool 5 minutes (don’t go longer; it needs to be warm when you add the lemon mixture).

Ingredients Filling

Directions

Do this while the crust is baking!

• Place the granulated sugar and finely grated lemon zest in a medium bowl. Using your fingers, massage zest into sugar until fragrant and lightly tinted yellow, about 1 minute.

• Add eggs and yolks and gently whisk just until combined.

• Add lemon juice and salt; stir to combine.

• Pour filling over slightly cooled crust and gently tap pan on counter to pop any air bubbles on surface. Bake until lemon mixture is set but still jiggles slightly when gently shaken, 20–25 minutes.

• Let lemon bar cool, then chill until cold, at least 4 hours.

• Using parchment paper overhang, lift lemon bar from pan and place on a cutting board. Cut into 25 squares.

• Dust lemon bars with powdered sugar just before serving.