Preheat the oven to 350 degrees F.

To make the crust: Blend 2 cups flour, softened butter, and 1/2 cup sugar in a medium bowl until well combined; press into the bottom of an ungreased 9x13-inch pan.

Bake in the preheated oven until firm and golden, about 15 minutes. Meanwhile, make the filling: Whisk remaining 1 1/2 cups sugar and 1/4 cup flour in a medium bowl. Whisk in eggs, then lemon juice until smooth; pour filling over the baked crust.

Bake in the preheated oven for 20 minutes. Set the pan aside to cool completely; the bars will firm up as they cool. When cooled, cut into uniform squares.