Step 1

Preheat oven to 350°F and line a 9x5-inch loaf pan with aluminum foil.

Step 2

Add flour, sugar and salt to a medium bowl and blend well. Add cool cubed butter and rub the butter into the dry ingredients with your fingertips until it is evenly distributed and the mixture resembles coarse crumbs that hold together in clumps when squeezed in your hand. Alternatively you can use a food processor to blend in the butter. Turn the mixture out into prepared pan and press it into an even layer, pushing it about 3/4-inch up the sides to create and edge crust that will hold in the filling. NOTE: if you don't make an edge crust, the filling will leak out and create a soggy bottom. Bake for 12-16 minutes until lightly golden.

Step 3

For the filling, whisk in eggs with sugar, lemon zest and salt until sugar is mostly dissolved. Whisk lemon juice until well combined, then whisk in flour until smooth.

Step 4

When crust is ready, reduce oven temperature to 325°F and slowly pour filling over hot crust. Bake for about 13-18 minutes until filling is just set with a slight wobble in the middle. Do not over-bake to ensure it will be smooth and creamy.

Step 5

Transfer to a wire rack and let cool completely, then cover and refrigerate until thoroughly chilled before slicing into squares. Dust with icing sugar just before serving.