Step by step

Method

5 steps

1. 1

   Heat the oven to 350°F. Line an 8-inch square pan with parchment, overhang on two sides. For the crust, cut ½ cup (113 g) cold cubed butter into 1 cup (125 g) flour, ¼ cup (50 g) powdered sugar, and a pinch of salt until coarse crumbs form — pea-sized bits of butter are fine. Press firmly into an even layer in the pan.

2. 2

   Bake the crust 15–18 minutes until the edges look lightly golden and the surface looks set and matte, not raw and shiny. Leave the oven on.

3. 3

   While the crust bakes, whisk 1 cup (200 g) sugar with 2 tablespoons flour. Whisk in 3 large eggs, ⅔ cup (160 ml) fresh lemon juice, and 1 tablespoon lemon zest until smooth — no egg streaks. Pour the filling over the hot crust right out of the oven so it starts setting from the bottom.

4. 4

   Bake 18–22 minutes until the center is just set — it should barely jiggle and look opaque, not liquid. A tiny wobble in the very middle is okay; it firms as it cools. Cool completely on a rack, then chill at least 1 hour.

5. 5

   Dust with powdered sugar, lift out by the parchment, and cut into 16 bars with a clean knife. You want a shortbread-like crust under a bright, silky lemon layer that cuts clean — not a soggy crust or a rubbery, overbaked filling.