Lemon bar

A lemon bar is a baked bar cookie built in two layers: a tender, pressed crust and a bright lemon filling that sets as it bakes. A University of Illinois Extension recipe shows the classic approach. The crust is made by combining flours, sugar, and salt with softened butter and lemon zest, then pressing the mixture evenly into the pan and baking it for 15 minutes at 350 degrees Fahrenheit.

The filling is simply whisked together from sugar, lemon zest, lemon juice, eggs, and a little flour until smooth. It is poured over the baked crust, and the pan goes back into the oven for 15 to 20 minutes, until the filling is set. Once cooled, the bars are cut into squares. The contrast between the buttery base and the tart, smooth top is what defines them.